Tutorial: Medieval Room Box
1/2 inch thick Owens Corning insulation foam. You can get it at Home Depot and similar stores.
Wood stain marker
X-Acto Knife/Box Cutter
Cut a floor and two walls. My floor is 6.5 x 7 inches. My window'ed wall is 7 x 8.5 inches, and the other wall is 7 x 8.5 inches.
I like to draw a grid on the foam very lightly with a pen so it doesn't indent into it. The grid doesn't have to be specific - just something to guide you straight - you don't have to make your bricks as big or as small as the grid. It helps me make sure I don't start out one size and finish with another.
I used the largest Dragon Shape from Gypsy Soul Laser Cuts. Place it in the center and trace around the outside, making sure it's smack dab in the middle of the floor. I added a circle around the dragon for added oomph using a compass.
I drew on random stones using my ballpoint pen, pressing harder and harder each time I go over the area with the pen, so that it breaks through the foam. Then I took a stain pen - designed for fixing odd spots on furniture and the like - and drew over the dragon, which melts the foam in that area, creating a stone-like texture, as well.
I added a window to one of the walls and then drew in the bricks around the window, followed by the stone in the wall itself. This method is repeated from the floor, and also on the other wall.
Grab a bit of aluminum foil, balled up and start pressing it into the floor and walls. Both sides of the walls, just the one side for the floor. This creates a stone texture that will come into play when you're painting later. The more you do to add texture, the more realism you can add.
I bought a pack of nail files from the dollar store and went through about ten of them for this project. Cut it to the shape that works best for you - I cut it in a sort of pointy shape, as you can see above. Then went through each crevice with the file, to separate each brick. This is tedious. But the end result is totally worth it.
I am lazy and used hot glue to attach the walls and floor - you should use PVA glue. Or hot glue. Don't let me tell you what to do.
Do the same to the floor - if you use straight angles, it's a little easier than these more random ones.
Then I painted the room. Use your own favourite painting techniques here. You could make the floor anything - you could make it scarier, or less scary, more mosaic - the sky is the limit! Here's the finished pictures: