Note: I really don’t think we need to do this. At least, I hope not.
You need to find the most optimal location. In doing so, you need to consider the terrain, water levels, and distance from other structures. This includes location of sewer and electrical lines.
Essentially, you want to have as much mass between your bomb shelter and the attack. After identifying potential nuclear bomb targets and where a likely blast wind will come from, determine a bomb shelter position that will serve the greatest protection.
…no hill or mountain would reduce the amount of fallout since it falls straight to the ground like snow. So, you just need to make sure you put your underground bomb shelter deep enough – 36 inches or more below the surface.
Put 30 days worth of food into your shelter (this article says three days worth, which seems awfully optimistic to me).
Along with your weather and satellite radio (in case anyone’s still broadcasting after the bombs) you should have books, writing materials and a portable DVD player with at least one copy of Dr. Strangelove.