Take Deep Breaths

When something gets you irritated, ensure you take deep breaths.  Removing yourself from the situation and taking 10 -20 seconds for yourself will allow you to re-group and not act on impulse.  Make sure to fill your lungs up slowly with air and expel the air like you are breathing through a straw.  Taking long breaths will help you to concentrate on the breath and not the situation that made you angry. 

Practicing breathing techniques on a regular basis will also keep you calm throughout the entire day.  Try taking yoga classes that involve breathing techniques.  These will not only develop your breathing muscles and lung capacity, but will also keep you relaxed and calm throughout the class and beyond.