I agree with Angela that you should not take any medicine if you can avoid it. Most problems come from bad habits, like eating too much or drinking caffeine, as mentioned in the article.

Also people should make sure that they get rid of any light that shines into their room, the darker, the better.
Furthermore it's advisable to stop watching TV or sitting at the computer about an hour before going to bed. The bright light tells the body that it's still daytime, so the body stays awake.

A better routine would be to read a book before going to bed. It's relaxing and therefore is a good preparation for sleep.

If someone German is reading this, here is another article that gives a few good tipps about how to have a better sleep:
http://www.schlafprobleme.org/blog/schlafprobleme/besser-schlafen-tipps.html

Sebastian