Set a timer on your Wi-Fi router.

Set your Wi-Fi router to automatically switch off in the evening and turn back on again in the morning. By setting a time limit on when you can use your connected devices, you can more easily unwind and prepare for a good night's sleep. 

WHY IT HELPS:
A time limit can help you make better and more focused use of your time. It gives you more time for relaxation later in the evening when you are closer to bedtime. Reducing digital use also limits your exposure to electromagnetic radiation. Several sleep lab studies indicate that radiation from Wi-Fi waves has a negative impact on sleep.