If you have no option, make a stand. Find the area with the least amount of vegetative growth. The less green there is, the less fuel there is for the fire. Avoid any valley, gully or canyon.
These are all a death trap in a wildfire. After picking your spot and making sure every member has one, lie face down. Cover any exposed body parts—particularly your neck and face, with dirt, clothing or a blanket. If the blanket or material is wet, all the better. This will help deter the wildfire. Once in place, lie still. Do not move or disturb your protective covering.