First thing you need to do is study the yorkie standard, go to AKC & YTCA to read about the standard. A breeding female needs to be at least 5lbs. Find yourself a mentor. The size of the dam & sire doesn't always matter on size of pups, you need to know the history of the lines you are breeding as well as the different generations in your breeding stock. Not sure how tiny you want, but remember that tinies can have more health issues. Please visit the websites I listed above, this will help you identify what color, coat, ear set, top line and so on needs to be.
