3. Stick to the basics.
Don't expect to whip up complex (or savory) meals. Pasta will quite literally mean plain pasta and oatmeal will quite literally mean plain oats. If you want enough calories to subsist on, flavor enhancers probably won't fit in the budget, so you might as well accept that everything is going to be considerably bland.
That being said, I did splurge on a $2.99 package of butter. A serving of butter (1 tablespoon) ended up costing just $0.10 and the package lasted the entire month. Plus, it provided a few more calories to my day-to-day diet.
If you're going to make room in the budget for a flavor enhancer, and you'll probably want to, choose something versatile — like butter or salt — that can be used on multiple foods.
4. Don't divide your dollars by days.
I took a big picture approach to the challenge, thinking about how much money I had to spend for the entire month, rather than on a day-by-day basis. It's important to buy for value, which often means buying in bulk, so sometimes I would spend $8 at the grocery store for supplies that would last several days — other days, I spent nothing.
Of course, if you take the big picture approach, you have to be diligent about tracking exactly how much you're spending to ensure you don't run out of money down the road.