Ah, the dreaded to-do list.
No one likes a to-do list. They always sound so aggressive, and mean. No one ever wants to actually follow through with one. How many times have you made a to-do list, gone two or three items down the list, and seen an item that you couldn't possibly do in the allotted time, only to give up and feel depressed for failing to be proactive? Maybe that's just me.
The solution, though is very simple: flexible schedules. As one of the masters of college scheduling, Cal Newport, would tell you, being an efficient student is all about ritual and habit.
My though goes along this line personally: If you're going to start a new to-do list, be prepared to keep doing them. find something you can't "do" today? Skip it. I know this must sound elementary, but I have personally failed to do whole to-do lists just from ignoring this simple rule.
Organizing your to-do list is also pretty important. make sure you organize things by importance and due date. Don't put things off--that's a sure way to double your future to-do list size.