1. Say “‘Frisco.”
No really, I dare you. Same with ‘San Fran’. If you’re saying ‘San Francisco’ often enough to need an abbreviation, just say ‘The City’- everyone will know which city you mean. And if you want a subtle way to tell if we’re from the area, just say ‘Frisco’ once and watch our reaction; see that look on our faces like the milk poured out lumpy? That means you’ve got yourself a bona fide local, but it’s already too late for you.