Try exercising as much as you're able, at least 2 hours before bedtime (exercising immediately before trying to sleep is useless; it'll keep you awake). Avoid caffeine, spicy food, grease, and sugar for several hours before bed. Drink warm milk if you can just before bed. Avoid loud, exciting, stimulation (TV, music, movies, video games) for a few hours before bed. We don't prepare ourselves for sleeping anymore, with our hectic, loud, stimulus-filled lifestyles.
I say avoid drugs and alcohol if you can; you don't want to become dependent on anything to help you sleep. That being said, most people find that a good dose of Benadryl makes them pleasantly drowsy, without the possible side effects of "sleep aids". I have allergies, so if I take it, not only do I sleep like a log, I wake up with clear sinuses
Good luck! AND it always helps to pray about it and tell God what you need.