Have you considered that it is likely that you could lose your girl? Breeding is a very complex, intricate process and everything doesn't always go well. I think yorkies are even more difficult to breed because of their size and genetic issues.
I would advise that you read as much as you can about the subject. You need to realize that you may lose your girl, that you may spend way more than you get for the pups, etc. For example, how long does a girl stay in heat? What is the time frame of a pregnancy? What can you do if a puppy has trouble breathing?
I have been reading about breeding for a year now and I only just realized that I know nothing. Anything can happen. Rather than breed her and put her through all the stress and anguish, why don't you try showing her? If she is within standard, you may then consider breeding her. If not, you can try fun things like agility, obedience, modeling or flyball. There is a lot less heartbreak in those things.
Think honestly about why you want to breed her and if it is the right thing for her. You need to be a responsible owner and the only way you can do that is to place her needs above your own.
I just want to add that I am not attacking you in any way. I am just trying to help
