Put a arrow shaft in the jig and loosen the two allen screws in the knobs under the the two magnets. Then let the clamp fall flush with the arrow shaft.You may have to help it by turning the knobs that the allen screws are in. This is all there is to adjusting the jig....... You should look at the three allen screws just in front of the knob that rotates you shaft and make sure it is set for the fletching configuration you desire. It has settings for 120, 90 and 75X105 degrees. Raise all the screws flush with the top of the hole, then screw down "ONLY" the one that is on your choice. the degrees are writen below each screw..... "Caution"!..... Do not take the screws all the way out! There is a small coil spring with a very tiny ball bearing in each hole. They have a way of getting lost very easy! I lost one and haven't found a replacement yet.