A lampshade assembly that includes only three parts, namely, a pleated lamp shade formed as a continuous resilient band having a plurality of notches in the pleat folds that extend inwardly towards the center of the band, a flexible member extending through apertures adjacent one end of the band, and a rigid support including a ring. The method of forming the lampshade assembly by the customer includes the one step procedure of moving the rigid support into the interior of the band and towards the flexible member until the ring of the support snaps into place in the notches. In the formed lampshade assembly, the ring pushes outwardly against the opposing inwardly directed force of the resilient band to hold the band, in conjunction with the flexible member, in a position in which the lampshade flares downwardly and outwardly.