Place a folded shirt on one of six cardboard sheets that you create. Trace the outline of the shirt with a ruler and pencil and cut all six pieces to the same size. Lay all six out vertically and place duct tape on the top row, while leaving the bottom row without the tape. Put your unfolded shirt facing down on the board, flip the left, flip the right, and bring up the center. Voila! Shirt Folding Board from Cardboard and Duct Tape [instructables]
