How do i change my life and turn it around for god?

Introspection: You have made the first step by realizing there are problems with your life. The best next step is to seek advice: trusted friend, counselor, minister or perhaps a psychologist. Then you can learn to make the right choices and get on a better track.

Make a decision : Make a decision to do so. Decide what is great about you & what you would like to address. Remember, you don't want to throw the baby out with the bathwater. Make a committment to improve yourself physically, emotionally and spiritually. Find a role model, sponsor, a confidant, etc - to obtain reality feedback & support from.