If kneading while happy ("making biscuits") hurts, just keep the tips of the claws trimmed. One of my cats has tiny little needle points for claws and she can't knead without poking right through my clothes and it hurts. Trimmed claws don't hurt.

If claw-attacking you while playing, stop playing and gently pinch the paws sideways (not top and bottom, but pinch the sides) while saying, "NO" in a firm voice. Pinching the sides of the paws like that retracts their claws, which helps them understand exactly what you're correcting. A friend of mine was amazed how gentle my little needle-point claw cat is with her claws while playing, and it's because I trained her this way.

If scratching furniture, provide a variety of many many acceptable things to scratch. Toys, carpet-covered climbing tower, cardboard scratching post, sisal scratching post. And just redirect them. Say NO when you see them scratching furniture and put a good scratching post near them. Praise when they scratch the post.