Quiet, dark bedroom, comfy pillow and mattress, no electronics, no cigars, cigarettes, alcohol or dope. No coffee, tea or sodas with caffeine, no sugar drinks, regular sleep and awake times, roughly 8 hours of sleep AND, no loads of food near bedtime. Least possible stress, possibly soothing music, or water sounds - ocean, seashore, stream or waterfall, or even a steady metronome. And... "meditation" before bed. Try regular exercise and a healthy, regular diet. Anything else? Oh, and quiet, quiet, quiet 1 hour before bed.
Make sure your room is really dark. No loud sounds, like tv or music. Drink warm milk, or soft chamomile tea. Getting a light massage right before you go to sleep helps too. I like a continuing sound, a fan, furnace etc.
Ok, this depends on how old you are, but act out something, quietly, like something you want to happen. Just say the words and don't actually start moving, if your older, read a book or listen to music.