Become aware of how you define yourself and defend yourself and your personal territory. For example, do you see yourself as a Liberal or a Conservative? An East Coast person or West Coast person? How do you defend that position? Notice how quickly a mug, parking place, or seat on the subway becomes "mine," and how you react when someone else takes it.
Check in on this process several times a day. In particular when you get irritated or upset, ask, "How am I defining myself or my personal territory at this moment?"— Jan Chozen Bays in How to Train a Wild Elephant and Other Adventures in Mindfulness