Before the test, always listen to your teacher and read books. Always take notes and ask question! If your teaches teaches you too fast, always ask them to slow down for you to write down the information you need. Find a quiet place to study or work.
Always exercise and stretch from time to time. A few days before the test, run a few lap to improve your brain thinking.
Further more, get a healthy breakfast every morning. Cereal and fruit are good for your body and brain.
Don’t just sleep early one day but three or four days before the test.