I think buying a Yorkie at 8 weeks is a mistake, toy breeds benefit greatly by being with a good breeder a minimum of 12 weeks, when I say "good breeder" I mean that a good breeder will do all the things necessary to insure proper socialization and beginning potty training and it's mother will teach inhibition of the biting reflex. If you choose to ignore the advice of the experts, be prepared to possibly have greater difficulty with housebreaking and biting.
But to answer you question, I think you can find many instructions on making a dog sweater out of a sock, it's perfect for young puppies.