How to Stop Destructive Chewing in Cats
Houseplants
Cats have a natural desire for greenery to chew, and your live houseplants might become a target. Some of these plants can be extremely toxic to cats, and for your cat's safety, you need to learn to recognize and get rid of these plants.
Check this list of toxic plants to see if any of your houseplants are on it, then either discard or make those plants completely unavailable to your cat.
Fabric and Leather Items
Wool chewing falls under the realm of OCD.2 For the kind of chewing behavior we're discussing here, the best way to discourage such behavior is to offer other "legal" chewing sources for your cat, e.g. chewable soft toys.
If you can't put away all the fabric and leather items your cat likes to chew on, try some bitter apple spray on the area where it usually chews, but test it first on a small hidden seam to ensure it doesn't stain.
Kittens
There's one item that works wonders with kittens' teething: plastic drinking straws, especially the large ones used for milkshakes. They provide the crunchy contact kittens need, and they make a great interactive toy.
You can derive lots of interactive play by teasing your kitten with the straw, then letting him "capture" it and watch him proudly carry around his "prey." Adult cats may remember their straws, so it's not unusual to see one of them batting one around the floor.
Clicker Training
Although most often effective with dogs, clicker training can be used in cats. Usually a small, hand-held device, the trainer or pet owner will make a clicking noise when the animal performs the desired behavior. In order for clicker training to be effective, the click must be immediately followed by a treat for the animal, so it learns to associate the action and the click with a positive experience. Eventually, the treat can be phased out.
Don't Hit or Yell
It's not effective in most animals, particularly not in cats, who will not associate bad behavior with the negative reinforcement you're intending.