When a big earthquake happens, aftershocks may continue for some time. After the aftershocks have stopped, evacuate to nearby parks or safe open spaces.
If you can't return to your home, please evacuate to an elementary or junior high school which is designated as an "Local disaster-prevention shelter" (Chiiki Bosai Kyoten).
But when the evacuation shelter has been damaged or become dangerous by fires, you should evacuate to "Wide-area evacuation site" (Koiki Hinan Basho) such as a large park or large expanses of land.
City of Yokohama sets up roadside signs which indicate the direction of the evacuation sites. Please check the signs around your home or your office.