creating new breed

Hello everyone, I am new here and I have a question. I'm looking for input on genetics. I want to start a new breed. I would like to have an end result of dark bottom half ( maybe spotted) and barring on hackles and saddle of a lighter color. I am thinking about Dominique roos over 3 different hens New Hampshire, Buff Orpington and Speckled Sussex. Should I take these crossed roos and breed them back to original hens or breed them to the cross hens then that offspring back to original hens or what? I want the 3 different lines for a spiral breeding program. Any sound help would be appreciated. I know it is going to take time, I'm just looking for a point in the right direction.
Thanx
Covert

 

Thanks. I'll try and find him
Joe