It is a cats nature to scratch their claws Im afraid! Do you have scratching posts/ mats around the house - you need plenty and can use catnip to get them to like using them if necessary? Just wondering if your cat is an indoor cat as I havent had too much of a problem with my outdoor cats who tend to use trees, fences more that my furniture of the walls.
Def invest in a scratching post - cats need to strop their claws on something and if you dont provide somewhere they'll find somewhere and that's usually where you don't want them to do it, particularly if he or she is an indoor cat. You can get a cheap one from Argos- less than £6
As others have said already it isn't likely that you will stop your cat scratching things as he needs to for keeping his claws sharp.
The best thing is to place a scratching post against the spots where he scratches most, but make sure that the post is a heavy one that the cat can put all his weight against and push on to scratch, if its unstable he won't use it.