I don't own a cat. I did when I was younger. I do watch my cat from hell. He said that if they don't clean they are stressed out. I'd first go to www.animalplanet.com/mycatfromhell , A good idea is also see a vet to see if something else is wrong. The cat may need exercise and medicine or just exercise.
Good Luck
Jim

Most cats groom themselves naturally but if your cat has long hair and it is matting the skin could be tender and inflammed. You may consider this and if the matting is excessive, have the vet sedate him and shave his hair and clean his skin. Bacterial or fungal infections can make the skin very tender and matting is one of the causes. As are fleas. Once the skin is healthy and the hair is growing back, you can begin brushing with a very soft brush on the areas your cat may like best. We have both long and short hair cats, some like brushing and combing, some don't but we do it on a regular basis anyway to prevent painful tangles and mats from forming.

ty for all ur suggestions

Our cat loves to be cleaned and brushed. But, I'm thinking..maybe your cat needs to learn to love the brush. Maybe sprinkle catnip on the brush bristles and for a few days don't even try to brush him, but just let him sniff the brush and feel good about it.

take the cat to a vet

Some of the brushes hurt when you press hard to get mats out. I have a brush that has on the upper part of it cutting blades that cut through mats. You don't press hard onto the cat.

also, if your cat has bad mats, you may have to consider having the cat groomed to avoid getting the mats in the first place. My first advice is to see a vet to find out if there are any anal problems that are causing pain so the cat can't groom well back there. The cat may also need his/her anal glands drained and when they are full they full like hemorrhoids that are raging. I have a cat that needs anal glands drained and some people are of the belief that cats never need this. Some do.