Wake Up!

In few last day, I always get problem to wake up in the morning even I use alarm clock. It's because I can't sleep early in the night. I believe when we early take to bed we can easy to wake up in the morning. But the problem is how I can sleep early in the night? I always got trouble when must sleep early, my eyes still open a couple hour even I was lay in my bed. Do you have tips for me?