I maintain my composure a little too much actually. I found myself in situations where I should have a feeling, reaction or behavior..etc but don't. Everyone reacts different I suppose. I don't do anything specific to prevent it, it's just not there.
However the one situation that I know I start to show my anger is when someone gets up in my face confrontationally, I bow up pretty quick and for that situation it would be expected by spectators. But other situations, perhaps I'm afraid to lose composure or draw attention to myself...not sure.
However there are many people that simply make a fool of themselves very easily such as ghetto folks which always amuse me.