Catahedron Costume

Step 5 Cut head opening, assemble tetrahedron

Pick one of the finished quilted triangles and cut a smaller upside-down triangle out of it, as an opening for the head. Use a wide sewing machine stitch to finish the cut edges. This was the part of the project I was least happy with the finished look of. If had it to do over again I would have made the head-triangle out of three smaller triangles with finished edges, rather than cutting into it and attempting to finish with sewing machine stitches. However fortunately the border doesn't really ever show while the cat is wearing the costume.

Using a color of thread that matches your binding, sew the edges together. Place triangles back to back (right sides out) and simply stitch along the edge. Though this will create a lip on the outside (showing edge) of the final product, because the triangles are already finished with binding I consider it aesthetically acceptable. Repeat process with the final triangle and the last two edges. After the edges are sewn together you should have a soft pyramid, almost capable of standing on its own.