How do you manage your temper?

Deep breaths never work. I end up shouting profanity and self harming. I might also start scribbling sporadic thoughts on a sheet of paper and it ends up looking like a jumbled up mess (although I normally do this when I'm embarassed about something, not when my head's steaming). I think I really need to try the deep breathing technique again, because I normally don't put in much effort into it and resort to my immature ways