Eat lots of good food. A tiny bit of healthy fat, a little more protein, and LOTS of fruit and vegetables. Also, some complex carbohydrates. People need carbohydrates for their emotional and intellectual stability but NOT refined carbohydrates. Give up one non-food (refined carbs and sugar, for instance) a week.

Excercise consistently, no matter what kind of excercise. DON'T go on a diet. Learn how to eat well.

If you eat for emotional reasons, (e.g. stress, boredom) identify those reasons and day by day, replace bad eating responses with other healthy responses (meditation, deep breathing, listening to music, etc.)

DON'T try to change everything at once. Make small changes and add to them.

Picture the new person underneath the old person that wants to emerge. Shed the old habits and let the new ones take over little by little.