Being prepared for tests does not just mean studying beforehand. It's important to come to tests with multiple writing utensils (in case one breaks or runs out of ink or lead), paper if it's an essay test and a calculator if it's math or science. Some teachers don't supply extras if you forget, and most students only carry enough for themselves. If you're using a pencil, make sure it has a good eraser and that it's already sharpened. Coming to tests prepared like this boosts confidence and helps you take advantage of valuable test time.