My recipe;
I bought six dove decoys that have the clothespin type attachment and a motorized dove decoy with the rotating wings. I painted them all gloss jet black. I made "t" shaped posts of heavy wire that I push into the ground and clip the decoys to them.
I bought a half yard of fake fur from Hobby Lobby that is slightly striped, so it could be a coon or any number of smallish predators. I cut the fabric so I have two pieces, 18" x 18", and used one to drape over my e-caller. The other is a spare.
I set up the mechanical decoy about 6"-8" in front of the covered caller and the other decoys scattered around, some on trees if there are any available.
I start with Crow Distress, then to Fight if needed. Works really well for me, even though the decoys are small for a Crow, I guess they think they are midget Crows...or something.
Ed