For one thing, it can help you get a more balanced perspective. When you find yourself thinking of a coworker as a single-cell life form, think what that would look like, picturing an amoeba sitting at a desk and talking on the phone. Or draw a picture. Doing so will take the edge off your fury or help defuse a tense situation.
Humor can also help when you find yourself being unreasonable. If you find yourself thinking that things not going your way is an unbearable indignity you shouldn’t have to tolerate, picture yourself as a god or goddess who always gets your way while others defer to you. The more detail you add, the more you’ll realize how unreasonable you are and how unimportant the things you’re angry about really are.
There are two cautions in using humor. First, don’t try to just “laugh off” your problems. Rather, use humor to help yourself face them more constructively. Second, don’t use harsh, sarcastic humor. Such humor is just another form of aggression.
What these techniques have in common is a refusal to take yourself too seriously.
Credit: American Psychological Association
See more: http://www.apa.org/helpcenter/controlling-anger.aspx