Something happens, and then you respond. In between there is a tiny gap, and most of us have trained ourselves to close it completely. Someone says the wrong thing and the reply is out before we have really thought about it. Then comes the regret.
The old texts have a word, titikṣā, for the ability to sit with discomfort without being thrown by it. Praise and criticism, a good day and a bad one, you feel all of it but you do not have to act on every passing wave. It is not about going numb. It is about not being quite so easy to move.
There is a plainer version from biology. That first hot rush of anger or craving is mostly chemistry, and a lot of it burns off within a minute or two if you stop feeding it with a story about how wronged you are. The message you would fire back in the heat of the moment is almost never the one you would send after a short walk.
So put the gap back in. One breath. A glass of water. A night's sleep before you answer the email that made your jaw tighten.
Try this: Next time you want to snap back at something, wait for one slow breath before you respond. Just the one.