I'm putting out a simple tutorial here for the pyramidebox. Use a standard 12"x12" bazill or similar type of paper. Draw the lines on the rear side of the paper, Cut the outerline ( where I have put 2cm ). Score at the rear side of the paper BUT the 5 cm lines must be scored at the front of the paper. Cut 4 x 2 triangles of pattern paper to decorate the inside and outside of the box if desired ( yellow triangle ) , Cut the square ( blue square ) in thick paper, and cut the square inside the square. Measure out where you need the hole in the box so it closes perfectly. Decorate and put together. Here is some pictures from scratch to finished product.
Photo from the village of Milicz, Poland