Levi,
If you read about daytime calling, chances are I wrote the article. The advice you've been given to this point is spot on. We identify den trees, old abandoned building, log jams, and any other place a coon may set up housekeeping.
We prefer to set the caller up fairly close to the base of the tree and on the side opposite of the den hole. This brings the coon completely out of the den hole and around to the backside of the tree where, when shot, it cannot easily make it back into the hole. You want them completely clear of the hole and where they won't fall back in when you shoot.
A den hole can be surprisingly small. I've seen coons squeeze out of holes no larger than 4-inches across. If they can slip their head through it, the rest can go, too.
Now, the set up. We locate as many holes in a tree as we can and set the caller up as described. (You'll be shocked when coons start appearing in places you didn't know about.) Then, using two of us, we set up with one where he can see the hole, and the other to his right or left, at a right angle, and with the sun not in his eyes. That way, as a matter of safety, you eliminate crossfire situations because, believe me, when things start popping, they can go fast. Of course, if you set up by yourself, position yourself where you can see the hole, but also where you can see the backside after the coon emerges.
Camo? Not mandatory, but you're in close to your targets - less than 10 yards - and they can see quite well in daylight. We have had them spot us and bug back into the tree, never to emerge again, so cammies and a face net sure don't hurt.
Calls? I encourage the use of e-callers for this, using downloadable coon fighting sounds. Any brand will work with the right sound. I discourage the use of hand calls for this type of calling, using coon fighting sounds, because responses here are for reasons vastly different than what you enjoy calling coyotes. Coyotes and cats are usually coming in out of hunger or curiosity. Coons are coming in because you've issued an invite to a fight and they want a piece of that action. Unless you're quite imbalanced, you do NOT want a mature boar coon zeroing in on your mouth hole.
BTW, I've only HEARD of one coyote attacking a caller on purpose. I've personally witnessed at least three instances where a coon responding to this calling turned toward one of us and charged with the intent to attack. Be safe.
Firepower? The Borlands at Minaska prefer .22 WMR's in semi-autos. My partner and I use a combination of power- he uses a .17 HMR, and I carry a 12 gauge using #4 buckshot 3-inch mags.
The reasons for this will become apparent the first time you have chargers. Coons, if they appear, will either come out slow and pensive, or on the fly. If they come out and offer a stationary shot, my gunner shoots them in the head with the HMR. If, by chance, they're beating feet to the dust up, I can pretty much take them off a high branch at out to 40 yards and then some. Doubles in close proximity to one another are a red letter opportunity. (NOTE: Have the crosshairs on the den hole before you hit the "go" button. You'll find out why soon enough.)
There's more to it, and I'll be giving a seminar on this type of hunting at the World Predator Hunting and Outdoor Exposition in Overland Park, Kansas if there's any chance you'll be that way in late August.
Let me know if you have any further questions. I'll be happy to help you out.
