1. Wake up at a fixed time every day. Even on weekends or off days! (Will set your biological clock.) 

2. Use your bed only for 3S (Sleep, sex and sickness). No working, no watching TV or mobile on the bed. 

3. 15 minute rule: If you cannot sleep within 15 minutes of going to bed, get out for 15 minutes and do a relaxing activity (meditation, light reading, music, etc.)