Don't call it San Fran

Other things not to do in San Francisco while you're there for pleasure or business is make a left turn onto Lombard from Hyde. You can't do it. It's illegal. There's even a sign right there saying so. You make a left turn from there and I can't drive to my friend's apartment because you people waiting to go down the "curviest street in the world" are blocking every avenue of approach. And the oil is slowly backing up into your rental car engines, and it fucking reeks.

For that matter, fuck Lombard St. If you want a street with as many curves and as good a view, take Vermont St., off the 101, south of the city.

1. The City. This is most common if you're in Silicon Valley. It may seem ambiguous, but what other city could it be referring to? Oakland? San Jose? Hah. We laugh at those places, much like New Yorkers laugh at, uh, every other city in the world. (Admittedly, this is probably because of ignorance of those places. I haven't been to San Jose in almost 2 years.)
2. The name of the neighborhood you're going to. This is more common among SF residents. It is a smaller city than many, but personalities of San Francisco neighborhoods vary widely. Try "Gonna grab a burrito in the Mission" or "Meet you at Tart to Tart in the Sunset".
3. SF is OK in text. Sometimes I use the airport code, SFO.
4. If the full name "San Francisco" is used, at least get rid of the assonance in the 2nd word. Shorten the "a" in "Francisco"; say "San Frinn-ciss-co" or "San Francis-co" but not "San Fraaaann-cisco". Except if you're Frank Sinatra; the chairman can sing it his way.