An Equal and Opposite Reaction
If, for instance, a guest at the bar starts yelling about having waited too long, rather than screaming back at him/her something like, “CAN’T YOU SEE I’M BUSY? YOU’LL HAVE TO WAIT YOUR TURN LIKE EVERYONE ELSE!” you instead look the customer in the eye and say, “I am terribly sorry, I’m really trying to be as fast as possible, please let me get you your drinks straight away so you don’t have to wait a second longer than necessary,” you’ll most likely find that the customer will be immediately soothed, and their anger will dissipate.
You’ll feel good about yourself if you follow this path. Promise.