Go over all or at least half the study material for the test at least 10 times thoroughly. Then wait about 5 minutes later then go over the other half then the whole thing again and again until you memorize it. Make sure you give yourself plenty of study time. Try to study if possible at least 2 days before testing. Then take a short break about 10-30 minutes then go over it one last time of the whole thing to see if you have it memorized.
Read a paragraph/section. Then, look away, and mentally try to paraphrase what you read. If you cannot do it, it means the material was going in one eye and out the other. Try again, trying to actively absorb it. Keep doing this section by section until it is absorbed. Then go back and review. You'll be surprised at how easily you can forget it. Keep persevering until you really have it.
I look through all my notes from class, and make a study guide. Once I finish that I read a section from the text book normally there are about 3-5 sections in my text book and read one a day. After that I look for a hard question to answer and write my answer in paragraph or essay form. I know it sounds like a lot, but I normally get an A+. Also pay attention and participate in class!