The secret is just to have a flimsy wing! There are two basic types of rigging wires on the E types (and all wing-warpers for that matter): 1) fixed static wires and 2) moving wires. The forward sets of wires (attached to the forward spar) on the Fokker Es (and I'll assume on the Pflaz) are static wires, "landing wires" on the top to keep the wings from collapsing downward on landing and "flying wires" on the bottom to keep them from folding up in flight. The rear cables are part of the wing-warping system and operate on two closed loops which start and end on the control lever on the undercarriage and pass through a set of double pulleys in the top pylon. As the cables travel in one direction, one edge of the wing is pulled up as the other edge is pulled down.

BTW, the four-pronged lever on the undercarriage is connected to the control column by a further pair of cables such that moving the stick from side to side rotates the undercarriage lever in the same direction.

I believe the travel on the wing-warping on the original was about 8" or so up and down. Flying one shouldn't be much of a problem for someone used to flying a 3-channel setup (throttle, rudder, and elevator) but if you think you'll just be able to turn with the wing-warping alone you might be in for an unpleasant surprise -- or have to plan on REALLY wide turns and not much ability to recover from a dumb thumbs episode or an sudden gust.