I used a wire cage last year, made it myself from hardware cloth. The ones I broke this year were accidental. I made a small hoop house for them in an isolated area with separate nests, since they went broody at the same time, and a fence around. I moved them there at night, and I guess I made a mistake putting them in the view of the main coop where they chose their nests. They spent the next 2-3 days pacing back and forth like 2 angry tigers trying to get out, not happy about my choice. I finally got tired and let them out, and they were no longer broody lol. When my next chicken got broody, I did the same thing and she was unhappy as well until I put a tarp in front so that she couldn't see the chicken coop anymore, and she immediately went back to the nest and has not got up since. I just let them give it a try to see how good they are, and give them like 5-6 eggs each. If you do want to break them, a wire cage is a good way to do it. My grandma used to stick them under a basket in a dark place without food or water for several days. I find it pretty cruel, so I would just use a plain wire cage in a place that doesn't offer any privacy, and would give them water and food, or at least water. They should be broken within a few days.
