Insomnia

Hm ....
make sure you go to bed at exactly the same time and wake up at exactly the same time every day.
Make sure your room doesn't get light too early, but that it's light when you're supposed to wake up (drawing heavy curtains can disturb your sleep rythm.)
Try to eliminate stress from your life, especially in the evening. (Don't use your computer before going to sleep, but read a romantic novel etc^^)
Try to exercise a bit everyday, to get yourself tired.
If you worry about something, maybe start a diary, or take some time of the day to talk about it with your friend.
If nothing helps, maybe see a doctor or a pyscologist.
Hope it gets better soon!