One of the most important things on that list is to buy my books. I buy mine online so I can get the best deal on a used book, which not only saves me money, but also keeps that book out of the landfill and decreases the need to print a new one. The only downside with buying used books is that you need to plan ahead. Unless you are willing to pay for quick shipping (I am not), it is important to buy your books at least 2 weeks in advanced. That way you get the best deals and they come before your teacher assigns a massive amount of reading on the first day of class.
The weekend after finals my roommate and I were sitting around watching TV when she suddenly starts talking about how expensive her textbooks are for the next quarter. It was horrifying to even be considering school at that point instead of enjoying break, but I ended up becoming curious and buying all of my books for the next quarter. I'm not sure I would plan ahead that much again. Getting the books in the mail throughout break has been slightly upsetting. But at least I'm done.
For more hints on places to look for used textbooks, go here. Happy textbook hunting.