Test Fit and Glue the Box Together When you have all your pieces cut, and have test fitted your windows and doors or door trim, test that your pieces are lined up correctly and fit together.
When the fit of the pieces is correct, apply glue to the bottom and back edge of one of the sides, and place it on the base piece (10 1/4 x 12 1/4) so that the bottom edge of the side matches the outside edge of the base, making a square face.
Prop up the side with a box or similar support, and apply glue to the back piece of the roombox (12 1/4 x 9 inch) Press the back against the back edge of the side and the base, making sure the edges are square. The back will cover the side edges and will sit on the base so that the back wall and the base edge line up square.Add glue to the edge of the final side and place it in position, propping it in place if necessary. Use a few pieces of low tack masking tape, or some other very low hold tape, to hold the pieces together until they dry (see photo).
Do not glue the roof piece to the sides until the interior paper is glued in place.
