People should know that it takes skills that must be practiced. And it may frequently take more than one concerted effort. Be prepared for slips. Research the benefits of change. For example, there are at least 50 benefits from exercise.
Most people can only cite about five.
Draw up a list of pluses and minuses that will come with change. Visualize the benefits. Don't go for a quick fix. Set a date for taking action. Develop a specific plan.