Having reverse-engineered an Origami T-Shirt I found on a bus seat, here is the method for creating this interesting folded paper object...
Ori-gami literally means "Folding Paper"
Generally the goal is to use a flat sheet of paper to create 3-dimensional objects such as flowers, animals structure or everyday objects and do so without cutting, tearing or gluing the paper although there are some easing of these restrictions.
Since paper deteriorates over time, the origins of Origami are still debatable as there are precious few remaining examples to provide provenance. It is clear however that the Japanese have embraced Origami (Japanese: "ori" = folding, "kami" = paper) most dearly, raising it to a true art form. We've all seen the 'Japanese crane' origami, -the quintessential staple subject of the Origami art. Origami paper (called "kami") is sold prepacked and often with colors, such is their love affair with the art that they provide a paper specifically dedicated to the craft.
Some months ago while riding a public transit bus I found an Origami object laying on a vacant seat. It was a folded bus transfer and in the form of a collared golf or sports shirt, a collared T-shirt. I was hooked.
The Origami T-Shirt
The folds seemed fairly easy and by reverse-engineering the folds I figured out the required steps. Here are my instructions to create your own Origami T-shirt using a rectangular piece of paper.
Begin with a Rectangular Length of Medium-Weight Paper
Step 1 and 2
Using a rectangular sheet of paper of medium thickness ('typing paper' etc.) that is at least three times longer than it is wide, place the paper with the desired 'FRONT SIDE' facing down. With blank paper this will not matter but if you are using a paper that has colors or printed designs (e.g., a coupon from a magazine, printed brochure cover or even paper currency) having a desired 'front' makes this step important. Some very interesting designs are created when using printed paper or paper currency.
In this tutorial, face down (Silver) will be the front of the finished origami T-Shirt. For clarity, the back of the shirt in this tutorial shall be tan/wheat colored.
Step 3 and 4
Unfold the lengthwise-folder sheet. Then fold each half inwards to meet evenly with the center fold created in the previous steps. Leave these 'wings' folded inwards.
Step 5: Flip Over
Flip the piece of paper so that the 'wings' are now facing the table surface as shown above.
Step 6: Form the Collar
With the folded 'wings' facing the table surface, fold back a narrow band on the desired 'top' of the shirt as shown above. Fold upwards back. Crease sharply. This will form the collar of the shirt.
Forming the Collar of the Origami T-Shirt
Step 7 and 8
Step 7: Flip the entire work once again so that the folded collar now faces the table surface.
Our folds are becoming increasingly complex from here forward. There are just several more remaining. Study the images for each step and proceed when ready.
For Step 8 we fold a corner of the downward-facing collar around so that the tip meets the center line. Note the sloping angle that is formed. Repeat the same fold for the other side of the collar, forming a matching set of folds and completing the left and right sides of the collar. Both tips meet point-to-point at the center-line.
Body of the Origami T-Shirt
With the collar facing upwards and away from you, visualize approximately one-thirds as shown with the red dashed lines. Fold bottom edge labeled EDGE "A" upward to meet with LINE "C" which forms a crease at "B." Using your thumbnail or a coin and by pressing firmly against a hard surface, deeply crease the fold at Crease "B."
Follow the direction "a)," "b)," and "c)," from the image above to perform this fold. Now, unfold Crease "B." Next we need to create inverted folds on each corner of Crease "B."
Forming the Sleeves of the Origami T-Shirt
Creating the inverted folds that form the sleeves looks difficult and it is hard to explain. There is only one way for the flaps to be folded. By pulling them out carefully and creasing, the sleeves are created. It will require some patience and experimentation to do this the first time. After that however, these folds become easy. A sharp crease at Crease "B" makes creating these sleeves much easier.
And now for the final fold:
Bring bottom edge Crease "B" up and tuck snugly under throat of collar, hold firmly with your thumb. Crease firmly at Line "C."
This completes the Origami T-Shirt how-to tutorial
(all graphics by author)