Complex sentence: The silhouette of the robot and throne were carefully drawn onto a piece of plywood to be used as a matte, using a pair of circular neon lights of a diameter corresponding with the matte's silhouette.
Split into simpler sentences: The silhouette of the robot and throne were carefully drawn onto a piece of plywood to be used as a matte. Using a pair of circular neon lights of a diameter corresponding with the matte's silhouette.