Pulling all-nighters during exams

Hello, I am done with two semesters and have had the realization that I require a decent amount of prep time before each exam for me to ace it. I have never sacrificed my 8 hours of sleep for anything. I have also never had coffee or something similar to help me through exams. I would like to know if you guys study the entire night before exams. If you do, what helps you pull it off and be at your best during the exam next day?