Even if the breed of your aggressor Russian blue, British blue, Siamese or Persian, don't despair, despite the fact that usually the representatives of these breeds have the most stable psyche.
Remember that all kittens scratch and bite. For them it is one of the ways of understanding the world. Also, cats by nature are carnivores, and playing, kitten, just work out the rules of conduct with the victim.
Don't Pat the cat at any point in time. Cats do not like displays of familiarity in their address, so they release the claws.
If the cat is unwell or hurt, don't even try to caress it, to regret. If purring the most seemingly healthy, but tries to slash you with their claws when you touch any part of his body, take him to the vet to check for whether the sick pet.
Learn not whether they live in the yard of your house stray cats. Your pet yesterday so gentle, it may just be frightened if you see or smell "foreign", and the whole hitherto unknown to him, the aggression will be directed against you. If possible, close him access to window and buy in the drugstore special spray with a "friendly" smell.
Think about what else might be scared of your cat. Maybe he doesn't like the smell of your toilet water or the noise of the repair coming from the neighbors. Note the tip of the tail: if he twitches or even goes from side to side, the cat at any moment to rush to you not with open arms.
Often play with the kitten. Try to during the games he didn't bite your exposed parts of the hands or feet. Otherwise later on he will perceive them as prey. If he is comfortably perched on your lap and purring quietly releases the claws, gently tuck them back into the pads of the paws to the cat, at first playing claws from pleasure, did not subsequently release them without reason.