Check your cat carefully to see if you can find a sore spot that causes her to bite you when you touch her. If you find a spot that is so tender your cat bites or protects when you touch her, take her to the vet for treatment. Is your cat spayed? Does she bite you only when she is in heat? Some female cats become excessively sensitive to petting while they are in heat, especially in the areas on the upper shoulders neck and on the back, just above the tail. If your cat is spayed, she may just become overstimulated when she is being petted. Those same areas, across the upper shoulders and across the top of the rump, are where nerve bundles are concentrated. Some cats seem to have too little padding between their skin and these nerve bundles, and they bite to make the irritation stop. Some cats merely lay their teeth on your hand to tell you they have had enough; others can bite quite hard.
If you do not plan to breed your cat, have her spayed. The hormone levels will drop off in a few weeks, and the excessive sensitivity should disappear. If your cat is spayed, pay attention to the circumstances leading up to her biting. If you can remember what happened just before she bit you, you can avoid future bites. If you notice that the cat bites you when you are petting her in one of her sensitive areas, avoid petting her there. Are you stroking her back vigorously? Try petting with little less enthusiasm. If you notice that she always bites after you have been petting her for 5 minutes or 15 minutes, set a time limit on your petting and stop before she becomes too excited.
When your cat bites you, hold absolutely still, and in a high, squeaky voice say, "Ouch!" Keep your hand still. If she doesn't let go, again, in a high squeaky voice, say, "Ouch!" When your cat lets go of your hand, put her on the floor and do not pet her for a while. Furnish her with a big stuffed toy so she can work off her pent-up desire to wrestle and bite. Cats and kittens display the limits of their tolerance both physically and vocally. When you say "ouch" in squeaky voice and stop moving your hand, your cat will know she is hurting you and will stop. Use the high, squeaky voice on kittens the first time they start playing too roughly with you. When siblings play too roughly, the victims squeal in pain and stop playing. This signals the aggressor that he is causing pain. Imitating the kitten's siblings is the quickest way to communicate with him. Do not roughhouse with your cat with your bare hand. By playing roughly with her, you are telling her that her rough behavior is okay with you. Substitute a large stuffed toy for your hand. Hold the toy and rub her belly with it, and when she starts attacking the toy, let go and allow her to kick and bite it instead of your hand.