Allot enough time for study.
Study is a major priority in college. While 6 hours may be too much for one student, it may be what is necessary for another. Therefore, you must examine your own needs and then allot your time appropriately.
Make use of your free hours between classes.
If your schedule permits, the hours between classes can be used to review notes before a class or to begin an assignment.
Study at the same time daily.
Having specific hours set aside each day will maintain the systematic organization of your schedule and keep you actively involved in studying.
Schedule a weekly review.
Plan to review each classes' notes from the beginning to end once a week. This only takes a short time and will reduce the amount of study time needed before an exam.
Schedule daily reviews.
Spend 15 - 20 minutes reviewing your notes immediately following class or when classes are done for the day. Again, this will reduce the amount of study time needed before an exam.
Account for project time.
Remember to allow an appropriate amount of time during the course of the week for long-term projects (i.e., papers, group projects, journals, etc.)
Allow for flexibility.
Although your schedule should be very systematic, you should allow for some flexibility. It is important not to over schedule thus allowing for a variety of "non-academic" activities.