What can I do to get to sleep then?
Sometimes people try medication such as sleeping tablets. The problem with these is that they work at a different level and override the normal systems.
Sleeping pills will knock a person out so that they sleep but they won't cure the problem of anxiety-related insomnia.
In general the best solution is to evaluate your situation and learn skills for focusing on the here and now rather than worrying about what might happen. Worry is the root cause of much insomnia that's not related to a medical problem.
Another common trigger for insomnia is that the person has experienced some kind of trauma and dreams or thoughts about this are creating raised arousal levels which, in turn, prevent sleeping. (There is more about this in the page about nightmares.)
One relatively simple method of reducing insomnia is to play Baroque music at a low level in the background whilst sleeping. I have suggested this in the past to several patients who were suffering severe PTSD (post traumatic stress disorder) and they reported that it definitey helped them to sleep.
The reasons for this involve the brain's ability to become entrained to the rhythm of the music. (You can read more about it on the page about Baroque music) But you don't need to understand why it works in order to try it. On the other hand if you happen to hate this type of music you will resent it and make matters worse!
Another reasonably simple aid to sleeping is to use a mindfulness meditation technique for which suitable downloads are available on this website (see Mindfulness)