This is going to sound kind of weird, but it usually works for me. When you close your eyes after you've had a long day and are tired and just turned out the lights, do you see little paterns of light that are still remaining in your eyes (I guess that's why they're there
)? They are usually just little patterns that you have to concentrate to see them, they're not just obvious. But anyways, if you actually concentrate on them, and follow them, it works by clearing your brain from all of your day to day problems and allowing you to relax. They won't put you to sleep directly, but they will clear your brain, which will eventually help you sleep.
If you don't know what I'm talking about, just look for them tonight, I bet you'll see them. It sounds weird, but it works for me.