Hop in a car with your mom and head north over the Golden Gate Bridge to Calistoga, where hot springs and mud baths are a plenty. Book an early morning massage at Indian Springs and enjoy an entire day of nothingness, lounging by the enormous geyser-fed, hot-hot-hot mineral pool. In the likely event you lose your ability to move your body due to extreme relaxation, I suggest you avoid the deep end.
Navigate your way across the Golden Gate Bridge, through some roads and over to Tiburon. Stroll about the town, have a beer and take a rest on the grass by the edge of the water. Set up camp and work on perfecting your handstands for several hours. Broken limbs, backs and egos are highly likely.
Take a ride to your nearest beach on a less desirable day – the foggier, the moodier, the overcastier the better. Enjoy exploring the eerie atmosphere, get lost in your solitude and consider the stark contrast of the beach on a sunny day. If I were you, I would avoid swimming, drowning and falling off cliffs. No one will find you.
Grab a group of good pals and head north over the Golden Gate Bridge to the top of Mount Tam. Follow the narrow, curvy roads up and up through the hills and trees. Pick one of the many scenic places to stop and hike on up just before sunset. May I suggest a nice bottle of wine to sip as the sun sets. Be sure to drink in moderation unless you actually want the hike down to get ugly.