Some students know how to manage time and balance everything very well. Others, not so much. Manage your time efficiently with a timer. Use a timer! There’s no need to sit in your room all day or all night studying. Just because you’re poring over your textbook for hours doesn’t mean it’s real study. Instead, use a timer to maximize each study session. This allows your brain to focus in a more targeted and effective way.
Motivation can be very individualized and there is no one way to do it right. You need to learn when to have fun. Working all the time is not fun. As I mentioned above, those were tips on how to maintain long hours of work without getting burnt out. But, you need to be able to have fun. Don't be that person who is always stressed about grades and exams. Just live in the moment and enjoy it. There's no point to having a 4.0 if you are miserable.