HI Marie. It was hard at the beginning, but it worked at the end. I too thought something was wrong! Keep trying to screw it to the end of your lens, eventually it will connect and screw properly to the lens.
As a Wide angle lens it just screws onto the end of the 18-55mm lens. I didn't think that it would work and I was worried that it would fall off. but it doesn't at all. To use as a Micro lens it requires another adapter.