If you are choosing your kitten from a litter, a few simple tips can help you pick well. Take your time and ask lots of questions. Have the kittens seen a veterinarian? Have they had a physical exam? Have they been vaccinated and de-wormed?
What sort of environment is the litter being kept in? Be wary if it's a shed or a pen away from the main house, because these kittens may have had little human contact. Cats have a very short socialization phase — between 4 to 16 weeks of age. A kitten that doesn't become used to the sights, sounds and smells of normal life by then may have problems later on.
However heart-wrenching a sight it may be, be careful about choosing a kitten that seems particularly nervous. This can be a sign of poor early socialization. Also, don't be tempted to take the smallest, weakest-looking kitten out of pity. This could be a very expensive mistake.
You should not take a kitten from her mother or her littermates too early. She needs to be at least six or seven weeks of age.
Once you choose a kitten and arrive home with your new pet, ask your veterinarian to recommend kitten food that meets the needs of your kitten.