Give blood - http://www.bloodcenters.org or 1-888-393-GIVE.
Donate money to an established organization.
Set up your own ‘Neighborhood Watch’ group though SF SAFE (415) 553-1984
Get to know your neighbors. Find out if anyone has specialized equipment, like a power generator or expertise such as medical knowledge, that might help in a crisis. Make arrangements to check on your neighbor’s home or pets if one of you is away when a disaster strikes.