How do you survive an artillery barrage?

Get low and hope it isn't air burst.

Finding a hole or trench makes you pretty much invincible against regular artillery, only a very lucky direct hit very close to or on top will kill you. Or unless the enemy is using airbust shells or some ridiculously powerful ammunition.

Jump in a hole. If there aren't any, just wait a few seconds and you'll have your pick. Press yourself against the bottom. Breathe, and keep your mouth open so you don't rupture your eardrums.

Blind freaking luck

you pray to all that is holy