I don't have any problems with sleeping, actually when I hit the sack I'm out dead for 8 hours untill my alarm wakes me up. But I have notice several things about helping myself sleep when I do have insomia (which is not often).
First thing to do is masturebate - it clears your mind so if you can't sleep because of thoughts running through your head or anxeity then this will help you out a bit.
Next make sure if you have an alarm clock that you don't always set it for the same time. Change it 5-10 mins each day. If its always the same then your body will get use to waking up at that time and you'll wake up an hour before your alarm clock because your body is getting ready to wake up.
Third, make sure you alarm clock is OUT OF REACH. If it is in reach you're very likely to "sleep tap" it and turn it off. I have done this countless times, my body just turns it off and my damn clock is HARD to turn off. I usually keep it on the other side of my room.
Fourth, NEVER look at the time. If you look at the time you're getting your mind to think about it and your waking yourself up even more.
Fifth, try several techniques if you can't get to sleep - holding your breath untill your about to pass out is good because it makes you forget what you're thinking about. Rubbing your eyes really hard is good, a glass of warm milk may do the trick. You can try counting sheep, its never worked for me though. If you can do it just try to think of nothing - its a sure fire way to fall asleep. If all else fails take 1 or 2 PM pain killers.
Hope this helps?