I think she's a good size to Breed. There are a few things I would do first.
Find a Breder and ask lots of questions. Read as much as you can about breeding, and search the net. For sure the male has to be smaller. And you need to get his generation pedigree as well. Here's one really good site.
http://www.debbiejensen.com/whelping.html
It really isn't as easy as one thinks. I too was going to Breed Princess
but I'm still not ready. Princess will be three in March. Our Vet, who is also a Yorkie Breeder said it's best to wait for them to turn two.
Good Luck to you!
