Ok', I'll do my best to explain it. The U shaped piece should have a hole at each end. Slide one end of the U on to the rod coming out of the drain(that rod is what attaches to the bottom of you stopper). Now slide on the part that makes the stopper go up and down, and slide the other end of you U shaped piece of metal on last. The U shaped piece of metal stops the ass'y from coming apart. I'm sorry if this sounds confusing...wish I could draw you a picture.