Make sure you understand what you're expected to know and listen for any helpful tips on preparing for the exam that may be provided by your professor. My colleague, Stephanie Webster, is planning to do an article and workshop on time management, so I won't go into great depth on the subject here, but most of us are really quite proficient at wasting time. Making a schedule and sticking to it helps. Also, find a place to study where you won't be distracted. For married students, the flash cards can provide an excellent means for involving your spouse in your study program.
Study groups can be a terrific help in law school.
Just be sure that each person shares the burden approximately equally. Also, there are some students who do not find study groups to be helpful. Don't overlook the possibility of tutoring and review sessions. And, for now, last but certainly not least, if you have real concerns along these lines, be assured that you're not alone. You might even want to take advantage of the fact that Stephanie and I are available to assist you.