How do I stay calm when the public takes their anger out on me?

All day, strangers unload the frustration of their whole day onto you, and you are expected to stay calm and kind through it. Doing that, over and over, quietly wears you down in a way people who have not done it will never understand. Naming that cost is fair. Politeness under fire is real labor. Here is what can steady you, almost none of it is actually about you. The person snapping at you is carrying their own bad day, their own troubles, and you happened to be in front of them. Their anger is a wave passing through, not a true judgment of you. You can let it pass without taking it inside. You cannot stop people from being difficult, but you can protect what happens within you. Take a breath before you respond, and remember you choose your own conduct even when they do not. Between their day and yours, put a small wall, and let their frustration stay on their side of it. Their storm does not have to become your weather.