Ok, pharmacy-outside-the-classroom time…
1) No sugar/caffeine intake after, say, 8pm. That’s the big one.
2) If you feel crappy, take a cold medication containing an antihistamine, such as diphenhydramine hydrochloride.
3) Melatonin is a dietary supplement linked to sleep that doesn’t have the physical addiction factor of diphenhydramine (note: PHYSICAL addiction does not = mental addiction, but mental is easier to brake). Give it a try.
4) Obviously there are Controlled Prescription Meds that help you fall/stay asleep such as Ambien and Lunesta. Try to stay away, there’s a reason they are controlled substances. But if that’s what it takes to get you to sleep, it’s not the worst thing in the world (if you don’t mind being addicted. Just never take more than prescribed, it’s dangerous).