You could also try regular excercise. As well as making you more tired it helps with stress levels and makes you more relaxed.
Decant quantities of calcium, magnesium, vit b6 and zinc can also help with insomnia, check to make sure these are in your diet.
It may sound dumb and childish but counting sheep can work (but not always). It's a kind of like a simple form of meditation that helps you clear the mind and relieve stress.