If you've waited until the night before, you'll never get it all learned anyway. Get a good night's rest before the exam. Eat a moderate breakfast or lunch. Avoid drinks with caffeine. Steer clear of fellow students who get tense.
Panic is contagious.
Get to the exam room early to settle and prepare your supplies and familiarize yourself with surroundings. Tense all your muscles for a moment, then suddenly relax them. This will help relieve tension. Take 3 deep breaths for the same results. Read directions and underline significant instructions.