The lap bar is pretty simple, once you’ve used it a couple of times. Loosen the lap bar knkob a few turns (counter clockwise) and pivot the short piece of wood to a vertical position with respect to the longer horizontal bar. Place the bar against the lower back of the harp, with the shorter, vertical piece of wood inside the sound box, through the lower string hole in the harp back.
The lap bar should be centered horizontally on the back of the harp, with the short piece centered in the lowest sound/string hole. Now reach over the top of the bar and turn the short piece of wood back parallel to the long bar. Tighten the knob so that the bar is attached to the back of the harp, with the back of the sound box becoming a sandwich between the long and short pieces of the lap bar. Once the bar is sufficiently tightened, the bar becomes a level surface, which rests across the top of the legs. The harp, being hooked to the bar, now stays in place.