Don't study everything BEFORE the day of the test, Because do you really expect to know everything by then. Re-Read over notes so you know what's on the test. Make sure you're aware of how many Questions are on the test.
When I study for a test I always read over my notes 1 or 2 times. Then I take a piece of paper or use my hand and try to answer the questions I wrote. (this only works if u write ur notes in question form (ex)what is the surface temperature of Neptune :answer)