Look at the Face on That One!
The highest teaching I can share is what our old Buddha friend asserted so long ago . . . "FORM IS EMPTY". In other words, as I understand it, if you react to the perceived attitude someone else may be sporting on their face, you are really only projecting. Think of it as if they are actually wearing a paper mask. In fact the word "persona" does mean "mask". But that's too deep for me.
Yet, if you do like to project your inner attitude on your face, then just know it's a choice. Certainly an option. Until, of course, it's not.
Just to say that we should take some care and be mindful about the kind of face we are wearing. Also, mindful and at choice about the kind of face we want to share socially. In time — take for example, a frowny face — if kept on too long it begins to grow on you so that you don't notice it at all, and it becomes a permanent feature of your presentation. Friends make this excuse for you: "Oh, he's not angry, that's just him. That's just the way he looks." Really? Like he don't have no choice? Well, I guess he don't if he's not self-aware enough to notice that there is a choice operating there. Even if it's a choice to keep that face going.
Bad faces are a form of social pollution. Once at a food market I passed a women who had the most grotesque facial expression. She was giving "Bad Face". Her head, I'm sure, was just fine; just, that face. Or, maybe her face matched her head? (Unknowable.) I was moved to take some action. Loud enough for her to hear I said to my partner, "Look at the face on that one." Suffice it to say our facially impaired shopper came out of herself.