Whisker City “Cat Scratcher”
Corrugated cardboard boxes that come with catnip.  Sprinkle the catnip over the cardboard and let the cat have at it! They’ll soon be sleeping and playing on the box and generally spending lots of time around it.  If they don’t take to it right away, run a feather toy over it to engage the cat’s nails on it.  They’ll soon learn that this is the appropriate place to scratch – NOT your furniture.  Unlike conventional scratching posts, it doesn’t feel like your carpeting or furniture, so there’s no confusion on the cat’s part.  It’s very successful!

Tree pieces with bark on them – hey, some people swear by this!

Transparent Double-Sided Tape Sheets
Sold at pet stores and hardware stores.  Most cats scratch the same place on the same piece of furniture over and over.  Place a sheet of this transparent tape over that place on your furniture.  The cat goes to scratch that place and their paws stick to it.  Cats HATE stickiness.  The tape is transparent, so guests can’t see it, but the cat will remember it’s there.  You can remove it after a few weeks.  If the cat returns to the spot after that, replace the piece of tape.

Nail Tips
Sold at pet stores (or over the internet with any animal website). $15 for 4 sets of nail tips which last for 3 months or so.  They make the nails more rounded so that they can’t catch on your furniture.

AND…
Clip the nails yourself (use regular human fingernail clippers and clip from the sides rather than the top downward).  Use a spray bottle to deter scratching.  Use positive reinforcement for good behavior.