What works for me is to not touch any work a few days before,(work relating to the topic)so that I can relax without the pressure of how I need to do this and that or I risk failing, and then I'll cram a day or two before the exam. I will do very little on the day on the exam because I can sometimes panic and skip over vital parts of the question. If you haven't learnt something in the five years you've had, you may struggle to learn it in one night, it might be better to be fresh and ready for the exam.Also go to sleep early, and get to school early so you don't miss the exam. Good luck!