It's been years since I've made one and I don't have pics of any I made but you can google it, they're out there. What's nice about a cage trap like that is you can catch several as opposed to a snare that only catches one. The trick is to find a place where the quail covey up. I used to put mine under a hopper grain bin we had on our farm. There was always a bit of grain laying around on the ground and the quail would be there looking for a free meal. The ones I made looked similar to this one, but not exactly:
They can get in, but can't figure out how to get back out.