First, make sure you're using the right feather in the jig, i.e., right wing feather in a right wing jig, and vice versa. Also, make sure that the nock receiver is for the wing clamp you have, i.e., right wing receiver for a right wing clamp and vice versa.
There are two adjustment screws on the jig. Loosen them, put a shaft in the jig and then lay the clamp on the arrow. Jockey it around, incorporating as much helical as you desire, until it lays flush along the shaft. Then, tighten the adjustment screws and have at it.
If you're trying to fletch a very small diameter shaft, like some carbons, you may not be able to use much helical. In fact, the curvature of the clamp may not match that of the small shaft diameter. Don't know. I don't fletch shafts that small, but it is a possibility. Good luck.