Gary-
1. Call lure, a lure that will draw the coyote to your set, usually a loud skunk based lure with a gland attractant, but skunk to get them froma distance to investigate the set. Carmens Canine Call one of the best.Put above the hole on the lip of the hole or up higher on some nearby vegation to get it up in the wind.Just a couple drops, very loud!!
2. Food based lure or bait, lure a liquid base of some type of tainted meat based preserved with glycerine or sodium benzonate to stop the rotting. Not rotten just tainted. To be put in the dirt hole for the coyote to work to get at. If left on top may induce a roll on. You want him to dig to get in out of the hole, every little drop.Bait is some form of solid tainted ground meat or combinations of meats or fish etc. O Gorman's Powder River Paste Bait a good one. A chunk the size of a quarter in the bottom of the hole covered with a wad of sheep wool is enough.
3. Gland lure or Urine same result, representing another canine presence. Same as your dog smellin every place another dog has been. Coyote turds refreshed with urine or ground coyote glands, which can be bought, layed near the set work fine. Most of your better call lures now are both call and gland lure to a certain extent. Most gland lures are a mix of scat urine and coyote glands ground to a paste.
Hope this helps.