Remember to take care of yourself. Sleeping is fundamental as it helps establishing long term memory.
Create a night time ritual that will help you fall asleep. Stop studying at least a couple of hours before bed. Learn how to relax, for example avoiding TV shows and video games (sigh) and leaning toward reading fiction, listening to music, chatting with a friend, drinking herbal teas, taking a hot bath.
Love yourself, no matter what.
Before a test help yourself focus and relax by taking slow, deep breaths. Build your self-confidence by telling yourself you’re awesome and super prepared till you believe it. Smile at yourself in a mirror when no one’s watching, even if smiling is the last thing you’d want to do. It will make you feel better (it triggers the release of endorphins in your brain!)
Above all, remember that you can only do your best!