There’s always some substantial meal under $5 everywhere. Seriously.
Buy scarves in Chinatown.
You’re never going to get a seat on a BART train to the East Bay unless you do the following: catch the next (always constant) train towards SFO and get off at Civic Center Station or 16th Street; wait for your train there. There’s your seat and time killer.
Avoid the embarrassment of needing a bathroom when you’re nowhere near a public place. Pop into fancy hotels like Hyatt or Hilton if within distance.
Greet the MUNI drivers.
The back door on Muni. And always step down.
Free WiFi down at the Embarcadero Ferry Building.