just get some half inch by half inch pieces of wood from home depot and set them so they can reach across your whole screen. when you're printing, depending on where your stencil is from the screen, tape the wood strip across to both sides of the screen 2 inches away from the start of the stencil. Here, the squeegee wont fall back, make a mess, or have to be grabbed at the bottom of the screen every time. simple as that and probably the cheapest.