First pic..... go to the point on that map where the pasture gets wider on the east side. At that point, run a fenceline east to west, to create a north block and a south block.  Split the south block into 2 sections, somewhere on the west side of your watering source. Split the north block into 4 long sections, with the sections divided by fencelines running north to south. 

Create a "permanent" cow lane between the north and south blocks, and then down to the watering source.  This will give you 6 lots with each having access to water. You can put on hand gates to open and close, to allow cows to access the pasture lot you wish to have them in.

Think about what 5 Head said about avoiding temporary fence. If you stick in posts, and use a single strand hi-tensile, I think this should work for you. 

Maybe you can use an online map program to measure lot size as I have suggested.  You can probably move that east-west fenceline north a bit, if you need to even up the lot sizes a bit.  

I hope this makes sense.