Grab ice cream at Birite Creamery, or a pastry and coffee at Tartine, and head on over to Dolores Park! You'll see a colorful bunch and this park, and the view is spectacular. Don't buy sweets from the vendors walking around unless you are looking to get high.
If you have access to a car, I'd highly recommend going across the Golden Gate Bridge to the Marine Headlands to get the view of the city from the other side. We try to take all our guests to this lookout spot - a must see if you haven't yet!