One issue that seems to arise every election is a shortage of poll workers. Lack of poll workers seems to translate into lack of ballots being distributed and/or counted properly and, ultimately, voter disenfranchisement is the result.
After the 2002 Election, I was determined to be more involved in this year's election by participating as a Poll Worker. I encourage you to do the same.
Also, if you speak another language besides English, you could be a big help as an interpreter.
I did a search on "poll workers san francisco" and found my local Department of Elections. The page gave me a phone number to call for more information. The recording at the number said that first-timers should come by City Hall in person in August. So that's what I'll do.