My cats have several things they are allowed to scratch - a nice tall scratching post (they need enough room to really stretch up and if it's not tall enough they will try to find something that is), a small kitty condo, and a horizontal scratcher. One of these days i'm going to get them a nice cat tree with perches and such. Like all trainable behavior issues, it really helps when you give them positive reinforcement when they use the post (play with them at the post, rub some catnip on it, tell them they are good and pretty when they use it, etc.) and when you redirect them to it when you catch them scratching elsewhere. If you do this consistently, most cats catch on pretty quick.
I clip my cats' claws whenever i see them get stuck to a scratching post... or to my shirt, heh. I've been clipping them since they were kittens and they are pretty good about it although they do squirm around a bit. I got some soft paws to try on Rajah when her allergies were making her scratch herself bald, but i didn't think i could get them applied properly - and they were pretty expensive for a set, so i stuck with clipping. Most of the time only their front paws need clipping - the backs only get done about twice a year because they are generally relatively dull. I would absolutely never declaw a cat unless it was medically necessary due to an infected paw or something like that - it's unecessary and can create other behavior issues that are much more difficult to control than scratching is.
I clip my cats' claws whenever i see them get stuck to a scratching post... or to my shirt, heh. I've been clipping them since they were kittens and they are pretty good about it although they do squirm around a bit. I got some soft paws to try on Rajah when her allergies were making her scratch herself bald, but i didn't think i could get them applied properly - and they were pretty expensive for a set, so i stuck with clipping. Most of the time only their front paws need clipping - the backs only get done about twice a year because they are generally relatively dull. I would absolutely never declaw a cat unless it was medically necessary due to an infected paw or something like that - it's unecessary and can create other behavior issues that are much more difficult to control than scratching is.