crank removal help

How do I remove the coterless cranks on my schwinn 20", I have this tool:
http://www.unicycle.com/shopping/shopexd.asp?id=421

You take that tool and pull the part that comes out…out. Then you thread the part with external threads into the threads on the inside of the crank near the axle. Sorry…you take the nut off the axle first. Anyways once thats in tight you thread the removable part into the part in the crank it it drives the crank away from the axle.

I had the tool on wrong, but i figured it out now.
thanks