Loosen the knobs on the Panel Holder clips. Slide the bottom panel clip with the beveled edge pointing up and tighten the locking knob. Place your panel onto the Panel Holder with the bottom edge on the bottom clip. While holding the panel, bring the top clip down on the top of the panel with the beveled edge of the Panel Holder clip pointing down. Now while firmly holding the top clip down one the panel, tighten the locking knob. Your panel should be firmly locked in place ready for painting. It will hold up to a 20" panel either 1/8' or 1/4' thick.