I used substrateless incubation last year, with 100% hatch rate with 3 clutches. I plan to do it again this year. It just seems idiot-proof

You take whatever size tub you're going to use, and cut the white plastic fluorescent light diffuser grating(found at Home Depot or Lowe's for $10 a sheet) to the same size as the inside. Then you mix up wetter than normal perlite mixture for under the grating(vermiculite is hard for me to get, so I used perlite, it keeps the water from sloshing around). The grating rests on top of the perlite, and the eggs go right on the grate. I just put all of this in the incubator until eggs arrived, and was good to go!

I did have a surprise clutch from my granite female(she was a rescue who was kept with a male her entire life), so I had to rush to get a tub set up. They all hatched fine too.