• Second-year Harvard student Sienna Santer grew a popular YouTube channel by sharing videos on topics like how to get into the prestigious university and what a day in her life is like.
• Now one year and 265,000 subscribers after she began posting to her channel in earnest, Santer said she fully supports herself financially through the money she earns online.
• Although Santer always dreamed of becoming a YouTuber, she didn't expect to grow so quickly, she said.
• Santer said she charges between $1,000 and $4,000 per sponsorship on YouTube and earns an average $3,000 per month from ads in her videos placed by Google.
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Sienna Santer is a second-year Harvard student with a popular YouTube channel where she shares videos - with her 265,000 subscribers - on topics like how she got into the prestigious university and what a day in her life is like.

Before Santer's channel blew up online (from her viral Harvard dorm room tour with 4.7 million views), the YouTube management group Table Rock Management reached out to her to see if she would be interested in signing with them.

"I had about 2,000 subscribers, but wasn't really doing anything with my channel," she said. "They reached out and said, 'Hey, we see potential in your channel. We think this could be something big.'"

Now Santer earns money from ads in her videos placed by Google, and by promoting brands like Audible and the vitamin company Care/of on her channel. Influencers like Santer earn the bulk of their money online by promoting products to their followers on Instagram and name-dropping brands on YouTube.

"It's helped me finance college," she said about her YouTube channel. "It's how I pay for my tuition - everything."

Santer is part of a rising trend of YouTubers becoming famous for sharing their college experiences - especially their move-in videos, which can rack up millions of views (and in Santer's case, thousands of dollars). Margot Lee, a Syracuse student with 425,000 YouTube subscribers, even teaches an informal pop-up class on becoming a professional influencer to her classmates (and shared her slides with Business Insider).

Earning money on YouTube from ads

On YouTube, creators with 1,000 subscribers and 4,000 watch hours are eligible to apply for YouTube's Partner Program and earn money from ads placed on videos by Google, called AdSense. How much a creator earns per video depends on views, watch time, and viewer demographics.

On average, Santer said she earns around $3,000 a month from AdSense.

"My channel has helped me deal with things a lot earlier than some of my friends and helped me a lot with money-management skills," she said. "I have checks for AdSense coming in the mail that I have put aside for taxes, retirement, savings."

The most she's earned a month from AdSense was around $6,000 during the month that her two videos went viral, she said.

"I signed up for the Partner Program so I could start earning money as soon as I met the threshold," she said, and learned how to do it by looking it up on YouTube.

She usually adds around two to three ads a video, if the video's over 10 minutes long, she said.

"I optimize my SEO by using rapidtags.io - you just input your title and then it gives you a whole list of tags to use for that title," she said. "I'll just copy and paste that, and then add my own tags that I think will do well. I also have a tool called Tube Buddy that lets me see how my tags are performing for each video."

For example, Santer checks if tags like, "college dorm tour" are helping her video's performance, by searching the tag on YouTube and seeing if her video is one of the top five to show up.

"I also choose my title very carefully, and put a lot of effort into making an aesthetically pleasing thumbnail," she said. "I know the power of thumbnails because I would often click on videos to watch simply because I liked their thumbnail."

How much she charges per sponsorship

Besides ads placed by Google, the second major way YouTube creators earn money is by promoting products through sponsored brand integrations. (Influencers also earn money promoting products on Instagram.)

Santer, who has 265,000 subscribers on YouTube, said she charges between $1,000 and $4,000 for a YouTube sponsorship, and her management group takes a 20% cut of all sponsorships they bring her. She hasn't done sponsored Instagram posts.

"All sponsorships I do are usually 60 to 120-second integrations" in a YouTube video, she said. "The only one that wasn't was a special video with Google which was to promote their Pixel 3, and that was a 3-minute whole video integration. They had a lot more say over that than a typical brand."

While Santer spends a lot of time working on her YouTube channel and influencer career, she also lets her management handle much of the business end.

"I have to trust them a lot," she said. "Many times they are very objective - it's up to me to decide whether an opportunity is worth it."

Santer is currently majoring in studies of women, gender, and sexuality at Harvard, with a minor in psychology, she said.

She wants to continue her YouTube channel after college, but doesn't see it being her full-time job.

"I'm drawn to the startup world and the creativity in that," she said. "After college, I'd want to either have my own startup or head marketing and branding for one. I want to also take my YouTube platform and do something good with it, whether that's a company, nonprofit, movement, I don't know. But I want to find what it is I am passionate about through this platform and maybe build a company around that."

Read more on Santer's YouTube career and how she got started here:

A Harvard student has become a YouTube star by sharing her college life, and it all started with people asking her how to get in