Manage deadlines
Part of getting work done is getting it done on time. When you get a new assignment, write the due date in your diary.
See what else you have due around that time and allocate a couple of nights to each essay, so you can start thinking about your ideas.
If you have trouble with deadlines, ask someone you know to keep you on track.
See also
Try to start work in advance. The more time you have, the less stressed you'll be.
