[danenania]

For people like me who often find "go to sleep early" impossible, try to get in an hour or so of solid exercise at least every couple of days--running, biking, lifting, or whatever--something that will fully exhaust you physically. And if possible, do it outside in the sun. This is the best way I've found to regulate sleeping patterns, and it also counteracts caffeine if I've had too much. I haven't found anything else that works as well.