Discipline is all about getting yourself to do things you resist doing, and/or not to do things you really want to do. So, one could rephrase the question: How do I get myself to do things I don’t want to do, and not to do things I want to do? There’s a recognition implicit in these questions that what we want to do and what we really ought to do are different. So, the first thing you need to do is define your wants and oughts, and perhaps rank them. Which wants are getting in the way of which oughts? It might help also to read what psychologists have learned about deferred gratification. The Marshmallow Test: Mastering Self-Control, by Walter Mischel (BF632 .M57 2014) is a good place to begin.