Yep doing something to tire your body or mind out will work, but also dont go to bed and lay there, reserve your time in bed only for sleeping for a month or two.
This means if you cant sleep, get up and watch TV, read somewhere, listen to music, anything you can do out of your bed for a while then try sleeping again in an hour or so. This lets your brain adjust to matching the idea of going to bed with sleeping.

Not fall asleep? Do soemthing.