How old is your cat? Soft paws is definitely a good idea to keep the damage to a minimum while you work on redirecting your cat's attention to the scratching posts. One method I have found helpful is to play with them using a feather toy. Then start moving the feather toy around and over the scratching posts.
Also, you may have already tried this, but I put catnip on the cardboard ones. My cats just love that.
Look into scratching posts covered in sisal instead of carpet. Your cat may like those. Make sure it is a sturdy post because cats don't want to feel like they are falling over when they scratch. I've gotten a couple from this vendor http://www.topcatproducts.com/
Sometimes it is hard to find the appropriate scratching posts. I have three and each is individual in their tastes.