While planting the suicide gear in the bathroom before Buckley comes in, Cooper tells Josh to tie the rope into a noose as they go to hide in the shower. Josh replies that he doesn't even know how to tie a noose. He must be a quick study, because in the 45 seconds or so that it would have taken Buckley to relieve himself and wash his hands, Josh has tied a perfect noose.
This movie is based on a popular Urban Legend, as was another 1998 movie, The Curve/Dead Man's Curve. See: http://www.snopes.com/college/admin/suicide.asp.