It takes about 30 days to develop a new habit. If you manage to do something you want to incorporate into your life for 30 days straight, without exceptions, you are supposed to be easily able to do it for the rest of your life. Read Steve Pavlina's
30 days to success. Then pick up
Million Dollar Habits by Brian Tracy and read the first few chapters where he explains how to make a new habit. It's all about habits. Just to be on the safe side though, I would not do 30 days but 60 days.