Take Our 21-Day Plan For Radical Self-Improvement

Believe it or not, as many as 50% of Americans say they don't floss every day. If you are one of those people, then make today the day you start doing it consistently.

How can you get in the habit?

Stanford psychologist B.J. Fogg is one of the foremost researchers on habit formation. The takeaway from all his work: Floss one tooth.

As in, if you're trying to form a habit, it can helpful to start as small as possible, with a minimum viable habit. The point, Fogg emphasizes, is to insert the structure of the activity in your day, rather than doing it perfectly every time. This way of thinking works for all habits, and it works for flossing, too — and if you floss the whole mouth, then you're doing even better.

Indeed, this core dental hygiene technique will clean your teeth and gums of plaque, protecting your teeth as you age and saving you on dental bills. Research suggests that flossing may even prevent heart disease, diabetes, and dementia.

For a wide range of ailments, exercise is an almost magical cure, which can "can improve memory and concentration, lessen sleep disorders, aid heart disease by lowering cholesterol and reducing blood pressure, help sexual problems such as erectile dysfunction, and raise low libido," notes Slate.

Just a little bit of exercise has huge benefits. Research shows that running just five to 10 minutes a day can add years to your life, and if you establish that minimum habit now of doing at least that, you can build on it. A seven-minute workout using interval training can make a huge difference.

Longer workouts are obviously great, too.

Think you're too busy to work out? Tell that to GE CEO Jeff Immelt, who gets up at 5:30 every morning for a cardio workout; or Xerox CEO Ursula Burns who has an hour of personal training at 6 a.m. twice a week; or Square CEO Jack Dorsey, who gets up similarly early to take six-mile jogs; or Starbucks CEO Howard Schultz, who likes to ride his bike every morning.

Psychologists have been studying "expressive writing," or journaling about difficult moments in your life, for a few decades. They've found that a few minutes journaling improves everything from mood to immune system to sporting performance.

It works for work, too: A Harvard Business School study found that people who wrote about their jobs improved their performance by 23%.

"When people have the opportunity to reflect, they experience a boost in self-efficacy," says HBS professor Francesca Gino. "They feel more confident that they can achieve things. As a result, they put more effort into what they're doing and what they learn."

So as a part of this life-improvement adventure, we're asking you to reflect on your day, plus on whatever journeys we send you on. You should also take the opportunity to look at the tasks that lie ahead and start making plans for the ones that require preparation.

If you find journaling to be useful, then we encourage you to keep it up for the rest of your life.

Let's start in on something scarce in modern life: reading an actual novel.

Why fiction? Because research shows that literature trains you in empathy (because its a simulation of social experience) and generally makes you a better person.

Lots of research suggests that reading trains you for living your life.

"The seemingly solitary act of holing up with a book . . . is actually an exercise in human interaction," Scientific American reports. "It can hone your social brain, so that when you put your book down you may be better prepared for camaraderie, collaboration, even love."

CEOs have a penchant for fiction: Elon Musk says "The Hitchhiker's Guide to the Galaxy" changed his life, and Jeff Bezos said the same of "The Remains of the Day."

Some highly readable suggestions, care of your writers: "Siddartha" by Herman Hesse, "White Teeth" by Zadie Smith, and "Pastoralia" by George Saunders.

We encourage you to read with a friend, as with this life improvement course, so it's more fun and you keep each other on track. Get together to discuss it when you're done, and you've got the beginnings of a book club — assuming you keep reading, as you should.

When you think of networking, you probably imagine grabbing a coffee or drink with a potential client, employer, or mentor for the benefit of your own career. But you might be missing out on valuable relationships in your own office.

Rather than eating lunch at your desk or with a buddy, strike up a conversation with an acquaintance and see if they'd like to grab something to eat.

Corporate coach Beth Weissenberger of the Handel Group has worked with executives at companies like GE and the New York Times, teaching them how to navigate office politics for maximum productivity and success. Office politics shouldn't mean gossiping and manipulation Weissenberger says. They should be about building meaningful relationships with the people you spend all day with.

The point of this assignment isn't just to have fun, though that's encouraged.

Museum visits come with a list of cognitive benefits that should help you be more creative, literate, well-rounded.

After visiting an art museum, students show stronger critical thinking skills and are more socially tolerant. Adults show similar benefits.

Visiting a museum can relieve mental fatigue and restore the ability to focus in the same way that the outdoors can, according to research from the University of Queensland in Australia.

Even more, going to a museum is a novelty-seeking venture, which triggers your brain to be open to learning. Not only does this provide long lasting cognitive benefits, it's also connected to one of the Big 5 personality traits — openness to experience. This is the trait most associated with creative achievement.

If you are a frequent museum-goer, try to pick one you haven't been to before. If your last museum experience was a class field trip, go with an open mind. See what you learn — and write about it later.

There are countless causes out there that could use your help, but if that isn't enough motivation, then let's look at how much volunteering will improve your life.

Engaging in generous behavior makes people feel good — as good as if their household income doubled, according to a study by Harvard Business School researchers.

And that strong feeling you get from connecting with those you're helping out is actually having a physical effect on your body. The oxytocin hormone our brain releases during moments of empathy lowers levels of the stress-causing cortisol hormone.

The good thing about all of these selfish reasons is that when you start volunteering, you'll probably like it and do it regularly and make the world a better place.

If you need some help finding a place where you can volunteer, check out Volunteer Match.

Money is dangerously easy to spend, and if you're not tracking it, you'll spend it even faster.

That's where startups come in. Over the past few years, a handful of companies have built super easy-to-use apps that take the "ugh" out of budgeting.

We recommend Mint, LearnVest, or the super-simple Level Money. Signing up with either will take about an hour.

The most beloved of these is Mint. Owned by Intuit, the makers of Quicken, Mint is a web and mobile app that gives you a complete overview of your financial health — letting you tie in your bank, credit card, investments and the rest of your dough.

Even better, a robust tutorial system will teach you how to become literate in personal finance in no time. Plus it's free.

And it works: Over the past three years, Mint's "Goals" feature has helped over one million users pay off over $20 billion in debt.

For more on the most popular budgeting apps, head here.

You may love that pair of ripped jeans from college, but there's no way you're wearing them out of the house. Chances are they're one of a dozen or more articles of clothing you don't need anymore.

Let go of your emotional attachment and give these clothes people who could actually use them (in the case of those ripped jeans, some organizations reuse fabric from torn clothes). You can donate to places like Goodwill, the Salvation Army, and Vietnam Veterans of America.

And don't think of this as a purely altruistic activity. If you have a particularly trendy item that you'd rather sell for some cash, check out sites like Tradesy, Twice, and Threadflip.

It's also good for your home to get rid of clutter and, conversely, good to make room for new clothes that you'll like a lot more.

In 1946, Gertrude Stein wrote "Everybody gets so much information all day long that they lose their common sense."

If only she knew what we face today ...

But there are some tricks to getting to inbox zero or at least something more sustainable — though it's going to take some work.

First, unsubscribe from all the email newsletters you've signed up for that you don't read — in most cases you can do it with just one or two clicks at the bottom of each email. You could also use a service like Unroll.Me, which lets you combine subscriptions into a digest email or unsubscribe from everything you forgot you even signed up for with one click. Next turn off your social media notification emails.

Then tackle that inbox. First delete or archive everything you can — any old newsletter, Groupon deal, or receipt. Then answer any message that can be responded to in under five minutes. If there are things that will take longer to respond to, use a system. File those emails in a "respond later" folder, and schedule a time to do so. You could also use an app like Boomerang that can make an email pop up in your inbox again after a certain amount of time — you can also use it to schedule emails to send later.

Adopt an approach that works for you. Chances are you know how, you just haven't taken the time to do it before. And if it's all too much, then declare email bankruptcy and start anew.

Going forward, try using filters to group important emails or automatically archive ones you don't want to delete, like receipts, but don't want in your inbox either.

There are three interpersonal ties in society: weak, strong, and absent.

The 1973 study "The Strength of Weak Ties" by Mark Granovetter of Johns Hopkins University found that it's not the strong ties you share with close friends and family that will most often get you ahead, but rather the weak ties you share with acquaintances.

Even though the members of your inner-circle may care about you deeply, they also tend to have access to the same people and information that you do.

So take some time to reconnect with three former friends or associates that you haven't talked to in years. Not only will it feel good to get back in touch, but there's a chance one or both of you will be helpful to the other.

It's up to you whether to call, send a letter, or send a text or online message. If you're unsure, email is probably the best choice as it represents a good compromise between efficiency and the potential for a meaningful message — and you can always arrange a follow-up call or meeting.

Steve Jobs used to say that the people with the most insight were those that had the biggest "bag of experiences."

If you want to add to your bag of experiences, a fast way is by seeing performing arts: classical music, theatre, dance, rock concerts, and the rest.

Live shows are also a way to tap directly into your culture, whether seeing new performances of old material or stuff that's never been done before.

Shows affect people. A 2002 survey found that attending such events increases cultural understanding, increases sense of connection to the community, and inspires personal creativity.

Go with friends or make it a date if you want to make it a bonding experience, too.

It's time to get out of town.

Heading to previously unknown locales — even if that means the next town over — is fantastic for you neurological and psychological well-being. A 2013 study found that travel reduces the risk of heart attack, lessens depression, and increases brain health.

As philosopher Alain de Betton would say, travel expands us.

"It is not necessarily at home that we best encounter our true selves," he wrote in "The Art of Travel." "The furniture insists that we cannot change because it does not; the domestic setting keeps us tethered to the person we are in ordinary life, who may not be who we essentially are."

If the cave paintings dotted around the world can tell us anything, it's that humans have been making art for over 40,000 years.

But the visual arts aren't just nice to look at, and the literary arts aren't just nice to read.

Decades of psychological research shows that making art has all sorts of benefits for people's well-being.

The research suggests that creating visual art has these effects:

• Improved well–being by decreasing negative emotions and increasing positive ones

• Improvements in flow and spontaneity, expression of grief, positive identity, and social networks

• Reductions in distress and negative emotions

And as we've mentioned before, the act of writing improves well-being, reduces anxiety, and even boosts your immune system.

With that in mind, let's set to work with creating a work of art. It's going to take some time — we're asking for at least 90 minutes. If you have some sketching skills, draw a still life on your kitchen table. If you're less practiced, use pastels to create some abstract art. If you're prefer to stay linguistic, drop a few poems describing the scenes that have happened in your life over the past week.

What matters is that you create.

The problem with planning your life is that there are an impossibly high number of variables — as LinkedIn founder Reid Hoffman and Apple CEO Tim Cook have noted.

It turns out the most effective way to make life plans is something called lifestyle design, a term favored "4-Hour Workweek" author Tim Ferriss and other productivity nerds. Instead of focusing on the status you want to attain, it's better to focus on the life you want to experience. Thinking about lifestyle design means considering the elements needed for us to flourish — like money, mobility, time, and relationships — and how we want those things to come together.

So let's take this day to envision the lifestyle you want in one year, five years, ten years. The simplest way to do that envisioning is with something called the perfect day exercise. Here's "The $100 Startup" author Chris Guillebeau's take:

In this classic exercise, you write out your idealized, perfect day in great detail, beginning from what time you get up and what you have for breakfast all the way through what you do for each hour of the day and who you talk to. The more detail you can add to the plan, the better.

Then you begin to make plans to adjust your life to get closer to the perfect day you've designed for yourself. If you take this exercise seriously, you may begin making more conscious decisions about how you spend your time and what you focus on. Even if you don't make a lot of changes, you'll learn a lot about yourself based on the information you acquire.

Now grab that journal and plot out what your perfect days will look like at these points in your life.

By doing this, you'll be better able to recognize opportunity when it knocks at your door.

This assignment may not be fun, but it's important.

Passwords get stolen, databases get hacked, and sometimes that means that someone can steal all your personal information — which not only can be a financial risk but also can result in the loss of irreplaceable information and photos. Unfortunately, almost everyone fails to follow good advice on passwords, not updating passwords after data breaches or as often as recommended and using the same passwords for multiple sites, in many cases using overly simple passwords.

At the very least, you should take this occasion to change all your passwords and make sure you have two-step verification enabled for everything, with backup codes printed and stored in a secure location.

Even better, you could set up a password manager that can create and store secure passwords for everything you do online. BI recommends 1Password or LastPass.

You just have to remember one "master password" and let the manager do the rest. Again, it won't be fun to set up, but your life will be vastly easier and safer if you do.

We all have things we want to accomplish in life, and, chances are, they won't be cheap.

If you plan to have a family, the USDA estimates that it costs about $250,000 to raise a child born in 2012 through age 16 — plus college tuition, which can top $200,000 at some schools.

Even if you don't have kids, it's recommended that everyone have around six month's worth of savings stored in case of an emergency. That's on top of retirement savings, which at this point in time generally need to cover about 30 years of living expenses.

It's time to think big. Get an idea of when your goals will become reality by listing:

- Your financial goals. These are major purchases or achievements like getting out of debt, buying a home, paying for a wedding, and taking that trip to the French Riviera.

- Your income. If you already have a budget, you should know this number cold, but if not, include your take-home pay as well as any other income streams you may have.

- Your debts. Do you have credit card debt, student loans, a car loan, or a mortgage? These payments are obligations you must meet, so take them into account when planning how much money goes toward your goals.

Then get specific by adding deadlines to achieve your goals, taking into account your debt and income. How much will you need to put toward that goal per month in order to achieve it by your self-imposed deadline?

Automate the process as much as possible by having money from your paycheck or checking account diverted into the appropriate savings accounts automatically through your bank and linking up your accounts to free services like Mint orLearnVest, which will keep track of your money and your progress for you.

Updating and improving your LinkedIn profile not only prepares you for your next job but also forces you to examine your career objectively.

Take a look at your page right now and view it the way a recruiter would. First of all, make sure your photo is a quality portrait that presents you the way you want to look in your industry. If you're going for a job on Wall Street, for example, you should be in formal wear; if you're a Bay Area techie, it's probably best to appear in a nice T-shirt.

Your Summary section should give a clear and concise description of who you are and what you have to offer. Get rid of any large blocks of texts, making sure that everything is easy to scan.

And make sure your page isn't boring. Use your personality in your writing and make sure you link to your relevant social media pages and websites, as well as any work you would like to share.

You can check out our full list of things you should be doing on LinkedIn but probably aren't.

And while you're at it, now is also a good time to update your résumé so that it's current and organized in a clean and concise way.

You'd be surprised at the connections you can make with highly influential people just by sending the right email.

To be clear, don't expect to set up a coffee date with President Obama anytime soon, but consider some of your favorite writers, entrepreneurs, artists, athletes — anyone influential that you would enjoy hearing from. You're going to have the best luck with someone who is currently out of the limelight, since they'll have an inbox that isn't flooded with media requests.

Personal finance author Ramit Sethi recommends sending an email that follows this format: Introduce yourself, reach a commonality (i.e. explain how has this person influenced you), and then ask a question.

Keep things concise, and be humble. And make sure that whatever you ask this person can't be answered with a simple Google search.

Once you get in touch with this person — whether you get a single-line emailed response or a meeting over coffee — be sure to follow up with them.

Sethi says that refined networking skills separate the mediocre from the truly successful and that the best $100 you can spend in a year will be on grabbing coffee with those who can help you advance your career.

You're almost there.

Your penultimate assignment is another that should be fun and also have some important benefits.

Go outside — a park will do, but if you can go on a hike, even better.

Spending time in nature lowers stress levels, restores mental energy, improves vision, and provides a creativity boost — along with much more.

For those reasons, psychiatrists in Japan are prescribing their patients shinrin yoku, or wilderness bathing.

Not only is going outside good for you, it should also be enjoyable. You can combine breaking a sweat and spending time with friends and do something that should leave you better off afterward.

Take some time to reflect on the past few weeks. Do you want to adapt new habits to your life? Do you need to make a radical change to reach your goals? Are you already on the right track? If you're asking these questions, then you're in the right mindset.

Take this final day to celebrate with friends and also practice a crucial skill.

Cooking at home "solves everything," according to bestselling author and James Beard Foundation Leadership Award winner Mark Bittman. He writes that people who eat at real food cooked at home eat significantly healthier meals and save money. Plus, research shows that food tastes better if you've worked to prepare it.

The reason we advocate "real food" — nothing processed or preserved or that comes prepared and just has to be heated up — is that it's the best way to eat well, according to researchers who extensively study all major diets. Healthy eating, of course, is one of the best ways to stay healthy.

As for what "ambitious" means, decided for yourself. If you never cook, cook; if you cook often, then cook an elaborate meal.

Once you learn to cook, it can be so rewarding that you won't stop. "It's as varied and challenging and rewarding a task as exists," Bittman writes.

Eating dinner with friends is about as good a bonding experience as there is, too. Regale them with stories from the past three weeks about how your life has changed for the better.

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