Some tips from the book Why We Sleep:

1. Go to bed and wake up at the same time each day. Set an alarm for bedtime
2. Exercise no later than two to three hours before bedtime.
3. Avoid caffeine and nicotine.
4. Avoid alcoholic drinks before bed.
5. Avoid large meals and beverages late at night.
6. Don’t take naps after 3 pm
7. Take a hot bath before bed
8. Dark bedroom, cool bedroom, gadget-free bedroom.
9. Get outside in natural sunlight for at least 30 minutes each day.
10. Don’t lie in bed awake. If you’re still awake after staying in bed for more than twenty minutes, get up.