Another method that helped many people a lot was using a citrus-flavored spray. All you have to do is spray the surface of the material you want to protect. These sprays work because cats have a natural aversion to citrus smells. To maintain the effect, reapply as needed. Because citrus-scented sprays are natural cat deterrents, you must never spray the product directly on your cat. These products are only intended to be sprayed on material surfaces. If you spray a couch or chair, do it before bed to be completely dry the next day when you sit on it.