- 1. Either a folded strip of 10 equilateral triangles
[see next page] or a printed net of ten equilateral triangles is required.
Accuracy is very desirable. Cut out the
__strip__of triangles. Do not detach the triangles. Make a strip of 10 triangles adjacent to each other. - 2. Lightly label the front and back of the strip as indicated.

Each back triangle is numbered 10 greater than the same triangle on the front. - 3. Score and fold each edge backwards and forwards so the creases are very flexible. Hold the strip as shown.
- 4. Fold triangles 1, 2, and 3 under triangles 4, 5, 6, 7, 8, 9, 10 as shown.
- 5. Fold triangles 7, 8, 9, 10 on top of triangle 6 as shown.
- 6. Place triangle 11 on top of triangle 19 rather than below it.
- 7. Lift triangle 20 and place it on top of triangle 11.
- 8. Curl a piece of tape around the right-hand edges of triangle 10 and triangle 11 beneath it.
- 9. The back of the flexagon should look like this.

- A. Use two hands to hold the flexagon in front of you.
- B. Select two adjacent triangles which do not share a folded/creased edge.

If you have selected correctly, you should be able to stick your finger into a "pocket" made by the overlapping triangles. But, you do not wish to do that. Pinch them together as directed in step C. - C. Pinch the two triangles together, common edge held tightest,

PINCH WITH YOUR LEFT HAND. - D. Push the extension of the pinched common edge down and to the center of the
flexagon.

As in the figure on the night, pinch triangles 4 and 12 together while pushing the edge shared by triangles 17 and 18. PUSH WITH THE POINTER FINGER OF YOUR RIGHT HAND. - E. The flexagon will begin to open from the center as do the petals of a flower. Open the flexagon from the edge and bend the triangles back and outward from the center as you would the petals of a flower.

If a flexagon has not been folded accurately, it may need "help"
flexing. This may be achieved by using a hole punch to remove the vertices of the
triangles. This decrease the friction when flexing.

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