Oh for a more generic listing while I think of it...
There are some things which've been prooven to have beneficial effect long term, rather than just "zomg I can't sleep tonight". Most of the stuff listed above is for a single night's restlessness.
- loose weight if overweight; gain weight if underweight (yes it exists jeeze)
- eat about 5 smaller meals a day instead of 1-3 larger ones
- exercise regularly, not just occasionally or before bed
- keep a strict sleep schedule, attempt to not deviate from it for any reason
- if yeu're tired and can't sleep, don't spend it in bed trying to sleep, yeu'll be gaining rest at the same time which'll slow down how quickly yeu tire, making it take much longer to actually sleep, so get up and do something that tires yeu as mentioned in above posts rather than lay there forever
- clear conscience; yeu don't have to be religious, but many people find it very hard to 'go to sleep angry' or feeling guilt. If yeu have to talk to a friend or even speak out loud to yeurself or whotever, do so, because if yeu feel guilt for any reason, it will keep yeu up all night
- doublecheck all little tasks required like chores; often restlessness can be attributed to just having a nagging feeling that yeu forgot to do something, it's worth doublechecking to be sure yeu didn't.
- don't overexhert yeurself. Seriously, as stupid as it sounds, it's fully possible to be "too tired to sleep" just as it is to be "too hungry to eat".
- avoid doing anything disturbing just before bed; while dreaming, yeur mind will attempt to break down things yeu saw during the day. Even if watching scarry movies late at night is traditional (and fun... I'm sooooo guilty of this XD ) it can lead to difficulties sleeping, or restlessness when asleep, or even waking up from nightmares (had that happen too >.< ). If yeu wait a few hours before sleeping after doing something like this, it helps a great deal as it won't be directly on yeur mind anymore
For quick referance, eating almost anything before bed works, the benfits of warm milk or turkey are vastly overrated. Yes they have chemical compounds in them which can be used to induce sleep, but in such miniscule amounts they have literally 0 effect as the liver just overrides them.
Oddly enough though, spicy food is a minor exception to this rule... even though something like jalapinos or cayenne may burn like hell at first (assumming yeu've not already built up a resistance), the reason WHY yeu build up a resistance to the heat is... it's actually a neurotoxin. Yes, yeu're literally eating poison. It's called Caspcian, which I probably spelled wrong but whotever, and a descent dose of it can help yeu sleep quickly.
Note that 'sleeping pills' and tranquilizers *DO NOT WORK*. Yes, they will knock yeu out, but a sleeping pill does NOT let yeu get any extra sleep. There's a difference between being knocked unconcious and actual restful sleep. Using sleeping pills and medication will only knock yeu out, meaning yeur body will not properly go into it's resting state, and yeu will not get REM sleep in most cases, meaning yeu'll still feel tired physically and mentally when yeu awake, and sure yeu were unconcious, but yeu got pretty much zero benefit out of doing so. The only time that yeu should be prescribed medications for this at all is if yeu can sleep fine but have issues getting to the sleep part, in which case a minor dose can be used to give yeu the nudge needed to unconcious, and yeu fall asleep after that. Far too often people rely on drugs these days to solve 'all their problems' which doesn't work most of the time... if properly prescribed for the right reasons, these CAN help in sleeping, but they won't do all the work for yeu. If yeu get given a large dosage, it's pretty much guaranteed not to work.