OK I have said I would put this on here for awhile now, well yesterday I set more cat sets and took a picture of what I call the hollow log set. I use this just for cats here, I think it would be good for fox too but I have never tried it on them, don't seem to catch coyotes either, not sure why yet but I will keep playing with it and see what I can do.
Here is one of the places I put this kind of set, this is a cedar draw and it narrows down right here, there is lots of cat sign right here to.
I put this right in the middle of the drainage so its visible from the bottom and the sides, then I dig my trap bed and place my trap, you can dig the bed and place the trap before you set the log cause you can put the log where ever you need it for the right distance from your trap.
Then you can finish off the trap bed and place your log where you want it, after you get it placed you can bait the hollow log, I place the bait in the hollow cavity and then place sheep wool on top of the bait, the hollow log allows the air to blow though and gets the scent into the air good too, I will give the side of the log a little cat urine too, here is the finished set.
I will usually put a flag some where close to it also, here is a picture of the finished set with a flag up wind of it.
I hope this helps out, if you have any questions please ask away.