Start with concrete times over which you have very little control. Enter your class times, lunch time and the time you need to wake up to go to class. What time should you go to sleep? This will depend on whether you are honest with yourself. Just under eight hours of sleep a night is the average for most adults (“What Are We Doing?” 60). It doesn't matter whether you need more or less time to get a good night's rest, but you should go to bed at whatever time allows you to feel fully awake and functional for next time..