You should fill your time by doing something fun all day long until it's time to actually sleep. Although this doesn't work sometimes and you should consider toughing it out. If you can find something really boring you sleep, that's good. Something like church tradition is slow as fuck and boring so go try watching them.
Other than that, probably coffee. I don't drink coffee daily so I don't know how much this helps.
Oh and to wake up on time, you should probably set a schedule for tomorrow and set your brain to not be late. I don't know how this really works but it works. Something like waking up before school even if you don't want to is an example of it.
Take small sleeps or whatever it's called. Please, this really helps. If you're really in need of sleep please do this. You can probably do this in classes without getting caught. Wouldn't recommend unless you're a top student and the teacher don't give a fuck.