How to unscrew a vintage camera lens?

I have an old Yashica campus that i don't use anymore and i have a nikon d5000, i have been looking in the macro reverse technique photography and they say i need a 50mm prime lense my old camera has it but it seems like i can't take it off… Is there anywyas to grab the lense?
By the way: if you don't know what reverse technique is please don't tell me that it won't work with my nikon d5000 haha i know that: P All I NEED TO KNOW IS how to unscrew the 50mm lens off my yashica is it possible?

If it's an SLR Yashica yes. I owned a couple of Yashikas and changed lenses all the time. They turn to the right from behind the camera - left if you're facing the camera.

The Yashica Campus has a fixed lens. You can't remove it.

Trixie is correct.No-can-do.

If you try to remove the lens, you'll break the camera as the lens is built-in.

You've actually got part of your solution in hand. Just use your kit 18-55mm lens, reversed with a Nikon-mount 52mm adaptor. These two examples are done with a D7000, but the technique and the lens are the same.

And here's one such adaptor.
http://www.amazon.com/...0054ENYDC/