Reach the DedSec Hackerspace.
Bring up your Nudle Map, and look for the Hackerspace marked just northwest of Mission Dolores Park, in San Francisco.
Ride or Die
Add a waypoint to provide a GPS route to this location, which shows a safe (but not always direct) route to an objective. Then locate a vehicle nearby (stealing or hijacking one are both viable options), and drive it to the Hackerspace. You could also try using a boat, which is quicker and offers excellent views.
On the Fly
Or simply Fast-Travel to the Stache & Vine clothing shop, which is only one block southwest of the Hackerspace. Then drive or stroll there.
Enter the games store known as GG&G (Gary’s Games & Glory).