This may be a bit much but i hope it'll help you:
1. Organize your notebooks, if you haven't already done so. This will make it much easier to locate reference materials such as class notes, handouts or reviews.
2. Start your studying early before your exams. Also start with your toughest material first while you are fresh. Budget your time well. Set up a long range plan to go through all material chapter by chapter. Do NOT Procrastinate!
3. Study a little bit each night. Do NOT try to cram in hours of one subject in a night. Twenty to thirty minutes should be sufficient for one subject at a time. Then, go to something else. Come back to the subjects that require further attention.
4. Doing your homework is not the same as studying! While homework assignments may be less during review periods, this does not mean that your studying is done when your homework is completed.
5. Use chapter reviews, worksheet packets, and flash cards to identify any ideas, phrases or concepts that are still difficult for you. Then set aside some special time to study these concepts alone.
6. Use study tools available to you. Study with someone else (try your parents...they'll love it and often will encourage you to study harder than your friends). Explain each major concept to study partner as though he/she were a five year old. Rehearse, review, repeat!
7. Use the time provided in the class and study sessions to ask questions. In order to do this, you will need to study outside of class to identify questions and problems that you still have. Keep a list of questions so that you remember them when you get to class.
8. Go through each chapter and try to pick out the major concepts, then try to write questions that you would ask someone to see if they understood those concepts.
9. Make up a story, the sillier the better, to help you remember the concepts. Make out a story board and then retell the story to yourself or someone else until you have perfected it. For example, the phrase Keep Him Doing Units During Commercial Minutes helps me memorize the order of the metric units from largest to smallest; Kilo, Hecto, Deca, UNIT [liter, gram, meter], Deci, Centi, and Milli.
10. Don't get overwhelmed. Give yourself credit for the incredible amount of material that you do know.
11. Get a good night's sleep before your exams.
12. Lastly, have a nice breakfast before you go to school.