Replacing a clutch cable is pretty straightforward and not much brand-related. You can remove first the one you have and take it with you to an official dealer to get a new one, or buy the new one beforehand and pray it is the right one. Generally you have to release the tension in the cable first, and then remove the barrel from the handle. After that you can remove the clutch end. Sorry I can't be more specific as I don't know wich bike you are talking about.
Raul