Let's talk about replacement. You probably know which of your habits are unhealthy...smoking, certain foods, procrastination. You probably also know that ending bad habits is no easy task.
One strategy I use are "Replacement Lists" (Download one here or write yours in a notebook). On one side, list the bad (food, habits, etc.). On the other, write down things you can do instead. Be specific as possible: Create separate lists for diet, exercise, rest, other activities and habits. These will help you set the intention for improving your life.