What Manny said.. Especially the glue part... Plus, one-inch thick Celluclay is pretty thick, lol.. It works best if you build it up in 1/4 to 1/2-inch thicknesses... If you have terrain that needs that height, it's best to build it up from underneath with blocks and such, and cover it with plaster-soaked cloth then apply the C-clay over it...
After the C-Clay is mixed, I always put it in a plastic bag, nip a small hole in it, and squeeze as much water out as I can through the hole... Then, I use a blow-dryer and paper towels to wick off even more after it's applied to the terrain..