This is a super simple build that took me 30 minutes the first time, 15 the second, and 10 the third. The final product is sturdy and comfortable enough for infrequent use. This is a good alternative to an expensive portfolio case for those who frequently need to hand in portions of their portfolio, but want to keep their main, more expensive, case in the mean time.

For this build you'll need:
Standard duct tape
A sharp knife
A piece of cardboard

The cardboard should be a bit (0-4 inches) wider than the longest edge of your paper/medium/work and 8 inches longer than twice the shortest edge of your paper/medium/work. That is:

Cardboard Width = Paper Length + margin of error
Cardboard Length = 2* Paper Width +8"

The extra eight inches are for the bottom, top, and flap.

**Note** This design creates a portfolio without sides, this is intentional as it can be laid out flat for easy insertion/removal of work.

Step 1: Bend It!

The first step is to bend your cardboard.

Measure the width (short side) of the pad of paper, board, artwork you'll be putting in your portfolio and mark that distance in from the sort side of your cardboard. (Pro tip: If you have the pad of paper you can use it as a measurement and a straight edge simultaneously by lying it on your cardboard and matching the long edge to the edge of your cardboard.)

The next section will be the bottom of the portfolio, so it's dimensions depend on the width of what you expect to be putting in your portfolio. I made it ~2" because i'm going to be putting a LOT of drawings in here.

After the bottom, there's another paper-width section, then the top (the same size as the bottom), and the flap (whatever's left over).

Use your sharp knife (carefully) by slicing along your lines only half way through the cardboard to make a hinge. Remember to never cut directly towards yourself of others. Cardboard looks awful with blood stains.

Fold the cardboard such that the cut side is on the outside of the hinge. This doesn't look very good, but that's what Duct Tape is for! If your cardboard is helpful, the internal structure of it should help keep your lines straight.

Step 2: Tape the Edges

Tape all the edges of the cardboard. This means the entire perimeter AND all of the cuts you just made. Tape the outside with the cardboard flat, but tape the cuts with the cardboard in it's desired bent position.

Step 3: Stab It!

Now you have a nice reinforced piece of cardboard, and you could just put your art in it and carry it around, but it'd be hard to hold and carry and would flop open at a moment's notice.

In order to make it more awesome we'll be adding a shoulder strap, hand hold, and latch. All of these will use the threaded-and-knotted duct tape ribbon method, which requires holes poked in strategic locations in your cardboard.

*NOTE -- DO NOT STAB YOURSELF*

Cut the holes:
Hand hold: Two horizontal (~4" apart) holes on the side away from you, forward of the vertical center line when you have it on the side that you'll carry it on most often.
Shoulder strap: One on the top a little forward of the vertical center line and one on the back/inside/side towards you behind the vertical center line
Latch: One hole on the vertical center line on the front/side away from you and one hole (also on the center line) on the flap.

Step 4: Fold It!

To make duct tape ribbon, take a single piece of duct tape and fold one side (lengthwise) over 1/3 such that 2/3 are stuck together and 1/3 is still exposed. Smooth this out, then fold the remaining third over. This makes a nicely sized strip with no sticky spots or frayable edges.

Step 5: Insert Here

Make three strips of duct tape ribbon, one ~8" and two ~12" long.

Insert the ends of the 8" long one through the handhold holes, and tie on the opposite side. Yay! A handhold!

Insert the end of one of the 12" long ones through the lower latch hole, and the other through the upper latch hole, tie both of these off. With the lower latch ribbon, make a knot that uses the entire ribbon except for a few inches. With the upper ribbon make a loop that goes around the knot in the lower ribbon and holds the flap closed. Don't tie this loop, just make a U of the right length, lay one end over the other, and tape together. Experiment with the orientation of this loop and the shape of the knot until it functions properly.

For the shoulder strap, take two very long (depending on where you put your holes this length will change, mine ended up at ~4') strips of duct tape, lay them together with a little over hang on each side. Fold the over hang over to get a wider strip with no sticky spots or frayable edges. Shove this forcibly through the shoulder strap holes and tie it off.

Step 6: Perfect Fit

The nice thing about this design is that's easily adjustable. If your shoulder strap doesn't fit, make it the length you want by tying off the upper end. Readjust until it fits you perfectly then chop off the excess.

Step 7: TaDa!

That's it! I hope you enjoy your new portfolio. It's cheaper than a store bought one and way more convenient and sturdy than just two pieces of cardboard taped together.

It's also WAY more fun to make in a group. Thanks to SelkeyMoonbeam, Sasha, and especially Annie (who was also my photographer) for hanging out and making this a super fun activity.