So, this is for my dad's Christmas present. I want to make a Star Wars Diorama. It's inside a 1gallon cookie jar. It'll be set on Tatooine, so tan and sandy. I'm aiming for three layers (bottom=rancor pit, middle=Jabba's Palace, top=Mos Eisley Cantina), but I don't know how to make the layers between them. I tried foam but I either make the circle too big and I have to cut it to fit where the cut is very noticeable, or I make the circle very small and there ends up being space all around the sides of the jar where it no longer looks realistic. I need help on how to make it look good and how to make the different layers.