I don't think you do water changes with a fishless cycle.
You only do water changes with a fish in cycle because you want to get ammonia readings but you don't want to poison the fish that's in your fish-in cycle.
With a fishless cycle you don't have to worry about poisoning a fish. You just have to keep testing the water with a test kit so that you know when you get your nitrite and nitrate readings. Then you just have to wait to get the right levels of ammonia, nitrate, and nitrite.
I'll also be using the piece of something method although since me and my mom don't have any shrimp on hand I'll be using a chunk of salmon in a couple of layers of pantyhose just to keep things neat and tidy. =]
Unfortunately the test-strip kit that I got doesn't test for ammonia so I'll have to get another kit that tests for it.
I'm cleaning and setting everything up today. I'll be posting about what happens on here a few weeks in. =]
Here's the best piece I've found on the topic. I actually found a lik to this piece on one of the threads here on bettafish.com.