About 80% of predator calling success is dictated by where you set up. You have to call where they are.
Use the wind to your advantage. Call with the wind either in you face or a crosswind. Coyotes are predictable in that they will circle downwind when approaching a call. Make sure you have openings to shoot on the downwind side of your setup.
Use the sun. Setup with the sun to you back. "A man's got to have an edge."
Keep calling even after you've shot a coyote. Many times they run in pairs. Right after you shoot the first one, give a distress call or a hurt-pup sound.