There are a few different ways to hang a Zapper on a double-sided hook, depending on the type of hook you have. If you have a screw-in hooks, simply screw the Zapper into the top rail. If you have an adjustable hooks, first adjust the height of the zapper so that it's at eye level, then screw it in. For hanging baskets, simply attach the hook to one side of the basket and loop the other side through the hole.