I am sure i will get grief for posting here since yesterday i said i don't often flake my spin... but i have, and i do flake my jib... so here goes...

Get a helper....(it is possible solo, but easier with help)
lay the sail out as flat as you can.
start at the foot... and fold in 2.5' - 3' sections on top of each other (accordion style) till you get in to the head of the sail.

Thats about all there is to it...