How To Think Ahead: Paint Yourself a Picture
Paint yourself a picture of the semester. Get a big desk-blotter style calendar, and sit down with your academic calendar for the year and all of your syllabi for your courses. On the calendar, mark down all of the important dates: paper due dates, exam schedules, vacations, etc. As more assignments come in, or as due dates change, make a note of them on your calendar. This way, nothing can take you by surprise.
Making Your Deadlines: Paint A Smaller Picture
How will you get all of your work done in time? Maybe the sight of your desk-blotter calendar sends shivers down your spine and leaves you feeling overwhelmed. Combat this feeling by looking at your schedule on a weekly and daily basis as well. Though there's no question that college keeps you very busy, when you take a look at what your time commitments are, you'll also notice where blocks of free time occur, too. While some of these must go to eating, sleeping, and hanging with friends, you should also use a fair amount of them for getting your work done.
One Thing At A Time, A Little Bit At A Time
The way to manage time most effectively is to avoid getting overwhelmed. You've already done a lot in this regard by making yourself aware of impending deadlines and by identifying the free time you have to meet those deadlines. What's important for you to do when you decide to utilize your free time for work is to focus on one thing at a time. Of course, you will probably have several assignments going on at the same time, and they'll all be in various states of progress on any given day, but when you sit down to do something, focus only on that thing.
How can you do this with so many competing and conflicting deadlines? Before you sit down to work, spend some time planning how you'll get everything done. The idea of a 10 page research paper can be overwhelming, and if you sit down for two hours with the idea "I'm going to work on my 10 page research paper," there's a good chance you might not get very far. After all, what can you realistically accomplish in two hours? However, if, before you sat down for your two hour study session, you had done some planning, figured out what all the smaller steps are that you need to take in order to have a 10 page research paper on the due date, you could accomplish more than you'd imagine. Break big tasks down into small ones, and set reasonable goals for yourself. In this way, you can get a lot done in many, little, less stressful steps.