This is not medical advice. See a doctor to check for underlying illness causing insomnia.

1) Concentrate on sleep hygiene first.

(http://www.nhs.uk/Livewell/insomnia/Documents/sleepdiary.pdf)

(http://www.cks.nhs.uk/insomnia/management/scenario_insomnia/...)

(http://www.papworthrssc.nhs.uk/sleep-services-hygiene.php)

You'll see that routine is important. Develop a "going to bed" routine. For some people that will be having a shower at wearing particular clothing. Others will have a warm milky drink then brush their teeth. The routine is important because it 'tells' your body that it's time for sleep.

2) You might find that sleep hygiene is still not enough. You could try one of the z drugs for a week to help kick your body back into a routine.

3) If that doesn't work you can try CBT for insomnia. It's hard to find quality CBT for insomnia.