Just kidding? the first thing my daughter put on upon comming home from the hospital was a baby bronco jersey I bought three months earlier, the only reason she didn't get wrapped in a broncos blanket right out of the womb, was because I had it delivered to the wrong address and didn't get it in time. My daughter not only loves the broncos at nearly age five, but she thinks that all football players are called "broncos" including the kids I coach at the local high school. You get early and be passionate and they will learn the right way.
I posted a picture of my daughter in her broncos jersey on this site four and a half years ago, but i can't find it. Oherwise I'd show you how it's done.