Some thoughts. Exercise. Eat healthy foods and stay well hydrated. Do something relaxing prior to sleeping and make sure your mind is not racing/stressed. Try to maintain a predictable schedule. Don't drink too much alcohol... I'm sure my neurology, sleep medicine, and psychiatry colleagues will have some thoughts too... :).
Good sleep hygiene. 1. Keep a regular bedtime & wakening time (to include weekends). Get up the same time each day, regardless of what time you fell asleep. 2. Make a regular, relaxing bedtime routine. Relaxing rituals prior to bedtime may include a warm bath or shower, aroma therapy, reading, or listening to gentle music. 3. Sleep in a dark, quiet, cool room on comfortable mattress & pillows.