Bad habits almost always arise because of a need..

Top Tip:

Identify why you have the need, make a firm decision to change the way you fulfill that need! The key is to find a non-bad substitute. If you get angry and break things - decide to eat chocolate and sit alone to calm down instead! You'll be making two decisions at the same time, one not to do the bad thing and one to do a good thing, the latter will help to reinforce the former.

Good luck, and if you get fat, decide to eat fruit instead of chocolate!