Ok, guys, I'm trying to help a friend. He has chickens and now of course a fox issue. Has a chicken coop, and a fenced area, but still loses a few when out. An idea of what and how to set these up. Never done it so to those who have, please chime in.

Go out and walk around the area. Usually, the fox doesn't take them very far before eating them. You'll see piles of feathers where they are taking them to eat. Or you will see worn trails that they are using to get close to the chickens. That's where you want to set.

Smaller footholds using a dirt hole set are usually the quickest way to catch fox but not always the most practical around the farm. A cage will serve you well, but I've also had success using dog proofs with a fruity bait in them to catch problem fox.

Dealing with about the same situation. Found the chickens but no trails. Put in a few dirtholes and a urine post yesterday so now we wait.

Cage with an egg or two. My son has become a fox/cat cage expert, lol. I honestly didn’t know they were that “easy” to catch in cage traps.

Coon size live trap work?

Yes, the bigger coon size cage (12x30) will work. Just give it a try. If fox is refusing a little taller cage may have to be used.

As I read the post I see you said. But still loses a few when out. Does that mean he looses chickens during the day? Not saying a fox will not get some in the day ,but it could be more than a fox. I had this happen and it was a neighbors dog.

snares on the trail to the coop.easy to see this time of year.

It is a fox, seen in day light yes.
Coon cuffs what do you bait with?

Coyotes wore my chickens out one year in the daylight

Even saw one laying in the edge of the woods by the yard waiting to ambush one

Don't have many foxes around but like others suggested, figure out the travel route