I'm not sure either Zanna, I haven't had to deal with broken wings yet. I had one little phoenix hen go under a chain link kennel and get her wing skewered on the fence where it bends. She was stuck that way but she healed quickly once I got her off.
I would probably try an ace bandage and safety pin, duct tape it, or sew it on, maybe wrapping the wing and then wrapping it around her body as well to hold it all in tightly. Then I would put her in a very small pet carrier where she could barely turn around so she can't move around and loosen it up so easily. I hope someone on the emergency forums has a better idea that has some experience with it. I don't know if you could put a collar type thing on thier necks like you do with dogs to keep them from pulling stuff off...seems like chickens would go crazy with that.