Staying calm while someone yells at you isn’t losing. It’s refusing to let them pick your mood.

Shouting is an attempt to set the temperature for both of you. Match it and the other person has effectively chosen how you spend the next hour, while whatever the argument was about disappears under the noise. Staying level is not submission; it keeps the decision about your own state with you.

Practice the mechanics, because they are physical: slower breath, quieter voice, feet still. Say you will keep talking once the shouting stops, then actually stop talking. Handle the substance later when you are both calm, and notice that you remember the details and they often do not.