Something I've found fascinating and useful within my own life is taking a habit or desire and over exposing it to what is desired, without necessarily fulfilling or indulging the desire. Obviously this takes a lot of discipline to do, because you are battling with your impules. However, this discipline not only toughens you magically and mentally, but also allows you to learn impulse control and also helps you banish the desire at times when it may not be appropriate to indulge it. Of course there are also other ways to get around a desire for something. This Sunday I bought a game for a friend that I really want to play. That friend will pay me back, and I'll get to play the game. I've addressed the desire without having to spend money for it.
And yet, at least for me, what appeals about over exposure to a desire is the simple fact that it can teach you an excellent skill in learning to deny yourself when its necessary to do so. Here's an exercise to try.
Go to a bookstore and go to the metaphysics section. Look at all the books you want. Pick them up, touch their spines, flip them open and think of how much you want to buy those books. The exposure to that desire initially will be a siren song. Put the book(s) back down and leave the store. Go back the next day, and the day after. Initially the desire to buy the books will increase, operating on the principle that if you're exposed to something seven times you are much more likely to buy it. And yet each time you will do your best to deny yourself.
If you give in and buy the book, give it to someone else, ideally someone who lives far away so you can't borrow the book, as the idea here is to promote discipline in denying your desire so that you can banish it.
Continue going in each day or every couple of days and exposing yourself to that desire. After a while the desire to buy the book will start to diminish because you will have conditioned yourself to not give into your desire. Eventually you'll be able to look at the book without feeling desire to buy it. It will just be another meaningless object, and so you will have banished your desire, while strengthening your discipline in being able to say no to your impulses. This can then be reapplied to any magical work you do, and you will have confidence in your skill at being able to focus on what you need to accomplish without being distracted by a fleeting fancy.
The ability to deny your desire is the strength to also enjoy it when you can indulge yourself. Over stimulation leads to desensitization, but desire can still be felt and turned back on as it were when the time is right. What this exercise shows you however is how to take desire and turn it into a tool that allows you to banish it by overexposure.