This is a big question with a lot of common sense answers, most of which you have probably already heard. Creating a structured schedule, joining a weight loss or exercise support group, following the approach of any number of health gurus—I’m sure you have heard these suggestions before. They each have their merit, but let’s see if I can help you go a little deeper and think outside the box on this question.
Psychologically speaking, there are several major influences on health behaviors including the habits of those we grew up with, our early experiences in physical education and sports (and whether these were positive or negative), and our genetics, temperaments and personalities. There is no one-size-fits-all answer.
If you have persistent difficulties making these changes, it may make sense to talk to a nutritionist, a health coach, or those in your circle who appear to be pretty successful at healthy living in their own personal lives. Ask specifically what they do to overcome the barriers of motivation and consistency that virtually all of us struggle with in making health changes. Try the ideas that make sense to you.
If you believe you have an entrenched pattern of unhealthy or self-destructive choices and you haven’t been able to overcome them on your own, I would encourage you to seek counseling or therapy. There may be important factors that are contributing to your self-destructive life patterns and there is a greater possibility of working these out if you seek a qualified professional counselor who has experience helping people change self-destructive lifestyles. Most important, don’t give up. There are as many solutions as problems in life and with persistence you will be able to find the ones that will work for you.