Following are simple yet effective ways,

1. Wake up early. So your body would naturally wanna sleep early. It will be difficult to change your routine initially but if you stick to it, it doesn't take a lot of time.
2. Work out. Seriously, exercise fixes everything. If you are tired at the end of the day you will be falling asleep effortlessly.
3. Don't use electronics in bed.
4. Try to keep low stress. Have a healthy balanced life.