- 1). Measure the size of the largest pieces of art that you will need to transport in your portfolio. Add 2 inches to the measurements.
- 2). Mark out the measurements of the two largest pieces of art on the corrugated cardboard box, and cut out two large rectangular pieces that are exactly the same size.
- 3). Cover the edges of the cardboard cutouts with duct tape to prevent paper cuts. The duct tape will also strengthen the portfolio. Duct tape the two pieces of cardboard together on three sides. Curl only the edges of the duct tape over the edges of the cardboard, leaving a gap between the boards. This will give you the space to put more than one piece of art between the boards.
- 4). Cover the exposed sticky side of the duct tape inside the case with a layer of duct tape. These added layers of duct tape will strengthen your art case.
- 5). Punch two holes in the top of both the cardboard sheets. The holes should be aligned.
- 6). Cut two equal lengths of ribbon. The ribbon should be as long as you want the handles to be. Thread a length of ribbon through one hole from the outside to the inside. Tie a knot in the end inside the art case. Do the same with the other end of the ribbon and the remaining hole on that side of the art case. Repeat with the other side of the art case.
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