Not sure I am right, but this is what I was told...
Hold a lazer with your write hand...
First
Find a dot along the plane line
Using The #1 Accumulator, then using the aiming the laser at that point, and do your piston motion. (with the right hand)
The lazer should be pointing at the same spot while you are doing the piston motion
Second
Stop doing the piston motion
Use the lazer pointing at the same dot with the extended right arm
Use the lazer to trace the plane line
Then
Do first and second simultaneously ...
Tracing the plane line and the pistol motion
Now you are fanning