Since it can inhibit sleep if it is consumed too close to going to bed, it is a good idea to stop all caffeine intake after 7 p.m. Although alcohol can promote drowsiness and is in fact a depressant, it can cause a restless sleep and may actually deprive you of necessary REM sleep. Exercising before bed will increase your heart rate and metabolism. Your body will need time to resume a resting heart rate and this will delay the onset of sleep. A glass of milk before bed really will help you become drowsy.
Milk contains an enzyme called tryptophan, which induces drowsiness.
Save your bed for sleep and sex. Psychologically it is not a good idea to get in the habit of studying, reading, or watching television in bed. Stop studying at least 30 minutes before you go to bed and use this time to relax instead. Thinking about what you have just read or written can prevent you from falling asleep. Turn the face of your clock away from your bed.