Talk wordy to me
There are few things better than a guy with a posh English accent speaking circles around gender-neutral-pronoun dissenters.
Cunning linguist (and adorably nerdy) Tom Scott explains why grammatical gender is dumb and why the gender-neutral pronoun "they" works.
Say you find yourself at a party, and you don't know the gender or pronouns of everyone present (I found myself in this situation just the other night).
DON'T: Presume anything, decide which gendered pronoun is correct to apply to someone, or ask invasive/personal/insulting questions (ie, "Are you a guy or a girl?").
DO: Politely ask either the person or a mutual friend which pronouns the person uses, if it's really that important. Or, and this works every time . . . avoid gendered pronouns altogether! If you find it awkward, it can be very fun to try to find a way to avoid using pronouns in conversation elegantly.
PRO TIP: Do it in a posh English accent!