I used to sleep late and get up late every morning for many years. Then I was able to change all that by going to bed early and rising early the next morning everyday. I used to sit with my legs crossed most of the time. Then I realized that I really shouldn't do that sitting in a church pew during Mass, and I was able to change that too. Now I actually feel better sitting anywhere without crossing my legs. The point I am getting at is that many of our sins are also habitual and you can change your habit to stop committing them again.