Reread notes taken in class each night.  You might be surprised how much this helps!

Make sure you can read and understad the meaning of new vocabulary words.  Try using them in a sentence until you become very familiar with them.

Make and use study cards.  Keep them handy at all times.  Whenever you have a few minutes, pull them out and review them.

Do not wait until the night before a test to study.  Study a little bit each night.