Almost everything of interest to tourists is along the waterfront—from the Embarcadero all the way to the Golden Gate Bridge (it makes a great bike ride). FYI, SF’s waterfront is probably the coolest in the world, with tons of great restaurants and interesting maritime history. I always walk up to Coit Tower from my hotel (usually in or around Union Square), and then down the other side to the Embarcadero. The walk takes me through Chinatown, which is overrated IMHO (it’s no match for the real thing)…but the strenous up-and-down makes for a great workout. Golden Gate Park is nice, as is the coast along Marin County, but you’ll need a car to get there. Alcatraz is a must-see. The cable cars are a hoot, but expect a long queue. Lombard Street is touristy, but then again, there’s nothing else quite the "Crookedest Street in the World" anywhere.

I live in the area, and totally agree with Homeskillet’s recommendations. A walk or ride up along the Embarcadero is very scenic, as it goes along all the piers and has great views of the Bay bridge, ships docked in the bay, and Alcatraz. Fishermans wharf/Pier 39 area is fun and touristy but great restaurants there. I like Chinatown (it has a lot of history) and the Haight-Ashbury area. Yes it is overrated and kind of cheesy, but the shopping is interesting and cheap.

The Telegraph Hill area is gorgeous and a must see. Also, walk or drive across the Golden Gate if you can, the view point on the other side is a good place for pictures. It’s an awesome city with a cool laid back vibe and I’m sure you’ll have fun whatever you do!

I just spent a week there in August.

Baker Beach was great, as was the park in the North Beach part of town.

Plan your days so you spend your time in one part of town one day, and then another part the next because it’s pretty big. Check who’s playing gigs around town, you might find something great.

Berkeley was fun, and I really liked Oakland. You have to ride the Cable Car even though it costs 5 bucks now. Watch the seals fight for space at Fisherman’s Wharf.

Chinatown is the place to go for souvenirs. You can go to the top of the Bank of America building and have a drink up there, great view!

have fun!

thanks everyone,
I wasn’t expecting such great and specific recommendations. I really appreciate it and I’m looking forward to my trip even more now!
I’ll post later to let you know how it went, but it may not be for a while. I leave 31st Oct and I’m there for a couple of weeks. I’m visiting another cousin who lives an hour away from SF in Davis. They own a horse farm there and they teach horse riding so that should be an experience too!
Thanks again for your advice.
xxx