How to get back into a sleep routine for school?

I'm 17 and I've always had a tough time sleeping. very light sleeper, I wake up 3 to 4 times per night. since in on christmas vacation from school I have been going to bed at 1am and getting up around 11am. school is in a week. and how do I get back to a routine of getting to sleep around 10pm and waking at 6 am? come next Sunday night ill get in bed at usual school night time of 9pm and probably will take 3 hours to fall asleep? how do I get to sleep quicker? I've always had a problem of taking 1 to 2 hours to fall asleep and now I'm off routine it will take 3 hours. and I don't want to chug nyquil cuz I used to be addicted to that and when I threw it away I couldn't sleep without it...so what do I do to get in a routine of sleeping 10pm to 6am and taking under an hour to fall asleep? thanks for answring!!