If your cat swipes at your furniture, gently take it to the post and help it get started by making scratching gestures. Use lots of praise. Keep your cat's nails well trimmed. Play with your cat often. Keep it active.
Claws are vital to the emotional well-being of a cat.
Scratching is not a misbehavior - it's part of being a cat. Your cat trusts you to protect him so please don't betray this trust by mutilating him.