Bobbi asked for some different tutorials, and I have been asked by others about my technique. Here is one of the ways I make habitats. This one is for fish, but can be switched up with different dirts for whatever you want. If someone has different twists on it, I am open to opinions. First I cut out a piece of plywood to the shape and size I want. Next I glue carving foam to the plywood and rasp and file it down the way I want it. Here I also put in indentations for some larger rocks I am adding. I use scrap carving foam from fish for this, but this time I had leftover larger pieces so it isn't pieced together. If there are any gaps I fill it with bondo. I then coat with fiberglass resin to seal the foam. I have heard of people using elmers glue but I have never tried that. I then usual hit it with tan paint since I am going to be putting sand on this so if the foam does show through it will blend in. I also apoxied my larger rocks down and added my drift wood. I now cover with elmers glue and start by sprinkling some larger pebbles over the base. Then I cover with the fine sand, press it down a bit and let it sit at least over night. When dry I dump off the loose sand, brush with a paint brush to remove any other loose sand. Since this is for fish I like to hit it with gloss. This is my preference, but like I said if you were doing a different dirt scene you could just leave it with black dirt and whatever else you want to add. Hope this is helpful to someone.