I almost never vote on the day of the election since I’m out of town or busy or whatnot. My wife and I went to City Hall in San Francisco to vote early today, since I’ll be out of the country on election day.
San Franciscans can vote at City Hall from now through election day. They’re open for voting from 8am to 5pm Monday through Friday and from 10am to 4pm on Saturdays and Sundays. If you’re not yet registered to vote, you can actually register and vote on the same day, but the deadline for that is Monday October 20 (tomorrow).