Well, it might be hard for you to follow this in the initial phase but setting a fixed timetable to bed and to raise helps a lot. This is a very good way to bring your healthy sleeping habit back to track. The thing is you have to follow this even on your weekends.
Just set an alarm clock to a certain time which you feel comfortable waking up at. As you get molded into a certain regular pattern of light and dark, this exposure is going to help for making a mindset. And you know what the early and fresh you wake up the more fit you are.