Step 1:
Prefold in half, then fold both parts in half three times. Unfold afterwards.

Step 6:
Fold both edges to the centerline.

Step 5:
Fold both corners to the center.

Step 2:
Fold over these two prefolded lines.

Step 4:
Prefold over these two lines.

Step 3:
Repeat steps 1 and 2 in this direction.

Step 10:
Fold these two triangle flaps backwards. And open the model by folding over the two longer outer lines.

Step 8:
Make zig zag folds over the prefolded lines.

Step 9:
Prefold over these lines, between the diamond shapes.

Step 7:
Fold both edges to the centerline. Then unfold the model completely.

Step 16:
Glue both ends together.

Step 15:
Repeat step 14 on these six spots.

Step 12:
Fold over these two lines.

Step 11:
Make an inside reverse fold on the four corners, use the prefolded lines as guidance. Then close the model again by folding over the two longer lines in the middle.

Step 14:
Fold the model into an angle on these two spots, make the same folds on the other side (mirror wise).
Use to prefolded lines and colored pattern as guidance to place the folds.

Step 13:
Prefold over the two outer lines and fold the model in half afterwards.

Step 17:
Fold the edges inwards over the prefolded line of step 13. Do the same on the other side of the model.