Go to bed and get up at consistent times even on the weekends.
Avoid heavy meals 3 hours before bedtime.
Exercise, but not within 3 hours of sleep, since your body needs to cool down in order for you to feel sleepy.
Avoid caffeine after lunchtime
Sleep in a dark, cool and quiet room
Use your bed only for sleeping and pre-sleeping activities, such as reading and being with the one you love
If you can’t fall asleep within a reasonable time, get up and do something relaxing, like reading