Start changing your sleep schedule, this will do wonder for you when you are back at school because you will not have that sleep deprived shock that most college students have coming back form break. A week before you have to go back simply set your alarm for the ideal time you want to wake up for classes.
Thoroughly read the first chapter in each of your textbook; when I mean thoroughly write notes flashcards and try your best to understand the material before hand. This way you can understand what the professor is talking about and clear up andy question you have.
Start planning your schedule; I usually come up with a schedule of things that are going on this semester from running, classes and eating or studying I plan it all down to a t. Of-course I do leave at least 2-3 hours a day usually in the evening to have some free time in which I watch tv, talk with people in the dorm or do some fun crafting.
Clean your room; this is a great way to start of the semester with a clean space in which you can study. If you are anything like me you can't be efficient with a messy room so I make sure my room is clean and de-cluttered.