If Inside

The most dangerous thing to do during the shaking of a quake is to try to leave the building because of the falling objects. Find a heavy object inside, and stay under it until it´s over.

In a Car

If you´re in your car during a quake, stop in the first available open area and stay inside until the quake is over. Most quakes only last a few seconds - the longest seconds of one´s life. Once the shaking stops, move with caution and avoid any bridges or overpasses and ramps that may have unseen damage.

If Outdoors

If you´re outside when an earthquake starts, move into the most open area available, away from buildings, street lights, and utility wires. Once in the open, just stay there until the shaking stops.

Quake Caused Fires

Fires are the most destructive force when a quake occurs near a modern city-moreso than the tremors. Especially if water mains and fire-fighting equipment are rendered useless, the fires burn unchecked.
In the past it was common for the doors of a fire-house to buckle during the on-set of a quake. The fire engines were trapped because the doors could not be opened. Today, most fire stations´ doors are connected to an earthquake detection system that will automatically raise all of the station´s doors on an average of 20 seconds before the tremors are actually felt by people.

Contact Plan

Develop an emergency communication plan in case family members are separated during a quake - a highly likely possibility during the day. Teach children how and when to call 911, police, or the fire department and which radio or tv station to tune into for emergency information.

Ask an out-of-state relative to serve as the family contact because after a quake it is easier to call long distance than local.

Water Valve

Your home´s water supply can easily become contaminated from other broken pipe sources, usually sewer lines, as a result of a quake. If you recall to shut your main water valve off immediately this will normally prevent that.

Fighting Plaque

Consumer reports suggests you use Listerine or a similar formulas, which rely on plant oils, to attack bacteria and fight plaque. They also recommend you speak with your dentist and try prescription mouth rinses & Perdex and/or Periogard & they work even better for figthing bacteria. Their active ingredient is chlorhexidine.

Housemates

If you´ve never experienced an earthquake, you´ll probably find it to be unnerving, that is, once you realize what´s happened. While quake tremors only last seconds, this can be a disorienting period of time. So, if you live with others or are at work with co-workers, round everyone up into a central location.
It´s easier if you have a prearranged meeting spot ahead of time, and you might consider conducting a periodic "drill" -- just like a fire drill. Aftershocks normally follow within minutes, although it could be longer. You might keep housemates/workmates together for 15 minutes in preparation before dispersing.