Always make sense of the problem as your first step: draw a picture, pull out key words, and identify the topic the question comes from as some ways of doing that.
Do the problem first and then look at the multiple choice answers, that's how the pros do it :)
Prepare for the test in small times multiple times in the weeks prior to the test. Cramming is the worst habit! You'll remember somethings for the next day and forget everything in the long run.
Make sure to ask question until you can explain the steps in your own words and complete similar problems successfully!