"duck and cover" doesn't work ... so don't hide under a table because you will be crushed ... instead, curl up in a fetal position and crouch down next to something large that will form a triangular void when it is crushed
it is best to be in a wooden structure because it "gives" ... and brick is safer than concrete
if in bed: roll off and stay on the floor close to the bed
try to get outside, but if unable to: curl up in the fetal position next to a sofa, or large chair
DO NOT stand in a doorway
STAY AWAY from the stairs
GET OUT OF YOUR CAR and just curl up in the fetal position next to it
There seems to be some conflict on wikipedia and snopes about this method being useful in the US because of building standards here and that we usually don't have major earthquakes. The American Red Cross still recommends "Drop, Cover, and Hold On!" but says "there is no dispute that the "void identification method" or the "Triangle of Life" may indeed be the best thing to teach in other countries where the risk of building collapse, even in moderate earthquakes, is great."
I guess the bottom line is do whatever makes sense to you ... muscle test and find out what resonates. You can get more detailed information as to "why" on the internet ... for me, I just want the bottom line if I am ever faced with an earthquake. I don't want to be thinking about why and second quessing myself when every second counts!