U.S. Geological Service Issues Report on California

They reported that there is a 99% chance that California will experience a 6.0+ earthquake in the next 30 years. Southern California's has a slightly higher chance for a large scale earthquake than northern California.

What that means is that every family needs to have a "plan." That plan should include contingencies for communicating their status (arrange for someone out of state to be your contact person). It's critical that each person have an emergency kit in their car that includes comfortable walking shoes, water, flashlight, batteries,thermal blanket, jacket, first aid kit and snacks that have a long shelf life (like Cliff bars).

You should also have a more elaborate kit at home that will sustain you and your family for at least seven days. There are many sites that have lists of supplies, etc.

Here's one that seems to be pretty thorough.  http://www.quakekare.com/emergency-preparedness/earthquake-preparedness.html

FYI: Central California is looking like one of the safer places to be during a major earthquake. Consider investing in Central California and the Central Valley.