For better sleep - exercise & get out of breath for at least half hour late afternoon / early evening (before 8pm) - could be gym, swimming, jogging, vacuuming the house or working out in the lounge to an exercise DVD;
Have a bowl of cereal or other carb-heavy snack before bed, with a glass of milk or hot milky (caffeine-free) drink. Jasmine or Camomile tea are relaxing too.
Make the bedroom cosy & make sure your bed & bedding are clean & comfortable; also have nice nightwear ready to put on;
Don't watch any violent or depressing TV or films at least an hour before bed; switch off the internet, put your mobile on 'silent', don't start reading a book...
In bed - get a puzzle book to do - not too difficult so you don't have to think too hard.. & then you may just get bored & fall asleep... if you really can't sleep then get up, walk around the house, make another milky drink & listen to some chill-out music. After 1/2 hr of that - go back to bed.
If you find it hard to fall asleep - don't panic, remember that just by lying still you are resting your mind & body anyway.
Try to stay in bed for 7 hours if possible - try to go to bed & get out of bed at the same time every day - use an alarm clock.
Don't be tempted to stay in bed past 9am at the latest if you have a lie in - if you are tired during the day then only sleep for maximum one hour.