How to make a Flexagon
First, you need to make your template.
The template is on the next page.
Second, cut AROUND the two pieces on the outline.
There will be 2 pieces with 19 triangles each.
Third, Make a double thickness by folding each piece in half and GLUING them shut. There should be 1 triangle that is NOT glued on each piece.
Fourth, glue the 2 strips together in a straight line by gluing the 2 triangles together.
Fifth, fold back and forth on ALL the lines and for ALL triangles.
Place the strip of 19 triangles with the side showing 6’s, 5’s and 4’s and the glue tab, *, to the left.
Fold the strip back on itself matching two 6’s, 5’s or 4’s that are next to each other and do that for the entire strip.
Now you have a strip of 10 triangles.
Place the strip without glue tabs (without these : *) facing up and with the “3” tab to the left. Fold BACK on the line between the third and forth triangles (2 and 1) — on the back four 2’s are together now. Flip the paper over. Fold BACK on the line where the next 2 and 1 meet. Now you should be able to see five 2’s.
Pull the 2 forward that is behind the 3. There should be six 2’s on top and one 1 to the side. Fold the 1 back and flip over. Now you should be able to see that the two glue tabs marked * are face-to-face. Glue them together.
Wait a little bit of time before flexing your flexagon.
How to flex your flexagon :
Fold the flexagon to bring three alternate corners together. The top of the flexagon will pop open if there is a new face to reveal. If it doesn’t pop open, flatten and try again with the other 3 corners.
You’re done !