Design an outside underground electric system???
If I were you I would:
A) Contact a few electricians to see if they will even do this for you.
B) If they will I would most definitely have them come out and layout the conduit runs for you.
C) I would NOT pull wire. Unless they will explain EXACTLY what wires to run and to where, you will almost certainly not get it right.
All this this can be done in 3 or 4 conduit runs, maybe less depending on terrain. Considering that, wire pulls are critical so that you don't waste time, money and material running redundant conductors.
The "hookups" as so many folks like to call them are NOT the hard part. The critical part is knowing what to run and where. Hooking up the boxes is easy.
Sometimes I feel like if I answer any more questions it is like someone trying to climb over a fence to jump off a bridge and me giving them a boost.