First we have to srew up the step-up rings together.
Afterwards come the step-down rings.
They should look like this:
Then we screw them together.
Attach them to the Fisheye Converter.
Now comes the camera.. Mount your fast lens to the camera.
And then carefully attach the Fisheye Converter with the rings to the front of the lens. Et Voila! You are ready to go!