Easier said than done. Realize that self mutilation is a very dangerous outlet for dealing with problems. There are other alternatives you can employ. I advice against the rubber band. It only reinforces the idea that you have to resolve your personal matters with pain. Try to refer to any hobbies. Utilize self-expression and use it as a tool to stray yourself from the thought. They provide the sufficiency to distract you when the urge is almost unbearable. Writing in a journal works, even meditation can be very calming. Try to amuse yourself, even in the littlest of things and keep yourself preoccupied with happy thoughts. It takes effort but even you owe yourself that.