That Zephyr Guy
crouton.net
So you just ask every single person on the street you come across what their pronouns are before simply asking for directions or when someone dropped their wallet? 'no idea if thats a man or a woman... 5 years later.. wallet is gone.. gender still not figured out'
and no, when people first meet, girls look like girls, guys look like guys, not always because of their hair or clothes, but voice, facial structures, body. That's how you usually notice.
If somebody corrects you, then you just change what you're using. You don't necessarily have to ask.
If you're worried someone might get offended, go with a gut feeling, or stick with "they".