Photo: Fireworks display folded by Bilge Ozel - you can read more about her First Origami Exhibition, held in Çorum, Turkey, from June 17-19, 2025.
Designer: Yami Yamauchi
Text Tutorial: Copyright 2026 by Bilge Ozel
Editing: Gemini 3
This model consists of a total of 12 Units. To make things easier at the beginning, 21cm paper can be used; however, larger or smaller sizes are also suitable. While the model can be made with a single color, a combination of different colors—using yellow, red, blue, green, or orange (instead of just red, for example)—is recommended to reflect the vibrant colors of fireworks.
One could use colors as follows: Units 1 to 4 could be yellow; Units 5 to 8 could be orange; Units 9 to 12 could be blue. You may need a few paper clips during the assembly of the Units. All 12 Units must be ready before you begin the assembly.
Part 1: Unit Construction
Step 1
Form a Waterbomb Base.
Step 2
Open the Waterbomb Base and position the paper so that the peaks of the diagonal creases are facing upward (mountain folds). Orient the paper so the edges are at the top and bottom, left and right (square orientation).
Step 3
You will now perform 4 cupboard folds (closet folds). First, fold the edge nearest you to meet the horizontal valley crease running through the center.
Step 4
Fold the opposite edge to the center horizontal valley crease. This completes two "cupboard doors" and creates a rectangular shape.
Step 5
Unfold these two cupboard doors. Fold the right and left edges to the vertical valley crease in the center. Another rectangular shape is formed, this time with the short edges at the top and bottom.
Step 6
Unfold the flaps you just made. Fold the edge nearest you to meet the horizontal valley crease that was created by the previous cupboard fold.
Step 7
Fold the edge furthest away from you to the horizontal valley crease created by the previous cupboard fold. Repeat the same process for the right and left edges.
Result: You will now have created 5 horizontal and 5 vertical valley creases.
Step 8
Unfold all creases and reform the paper into a Waterbomb Base using the existing folds.
Step 9
Position the Waterbomb Base with the open ends facing you. On the top surface, you will see two horizontal lines and vertical lines near the right and left edges. The lines closest to the edges are shorter than the others. Now, fold the edge nearest you towards the opposite side. This fold should occur at the horizontal line furthest from you. When this edge is folded away from you, it should align perfectly with the closed tip of the Waterbomb Base. As you do this, two new hinges should form along the upper-right and upper-left diagonals. A pentagonal shape, resembling a house, is now formed on top of the triangle.
Step 10
Flip the paper over and repeat Step 9 on this side. The main shape of the model is now a pentagon with two free-flapping parts on the side facing you. This pentagonal shape has 4 wings (two on the right, two on the left), with a total of 4 layers.
Step 11
We will now perform what is known in origami as a "squash fold." Focus on the right section of the shape. Find the horizontal line on the surface of the model running closest to you. Fold the bottom-right corner of the pentagon into a triangle up to this line. Fold only the top flap. Do not try to fold both flaps at once, as the paper will become too thick and the creases will not be sharp. The hinge of this triangular fold points to the "4:30" position.
Step 12
Unfold the triangular fold you just made and turn the newly formed valley crease into a mountain fold. The hinged edge that was facing directly forward when folded now faces directly to the right. Fold the edge facing you towards the opposite side along the horizontal line closest to you. Ensure you are only taking one layer. While folding, press down on that small right-facing edge with your finger to turn it into a valley fold. Since you tightened the triangle's own hinge, it is already a mountain fold.
When you press the piece flat, a small "hat" shape is formed with its opening on the left. The hat is triangular, and its pointed tip faces right. Additionally, a rectangular hollow is formed in this part of the pentagon. One of the short sides of the rectangle faces the opening of the hat. The long sides of the triangle should be equal; if not, adjust them.
Step 13
Repeat the squash fold on the left side of the pentagon. You will now have the two hats pointing in opposite directions. Between the hat shapes, there will be four small squares making up the bottom center area of the model.
Step 14
Flip the paper over and repeat Steps 11, 12, and 13 on this side. The overall shape of the paper has now become a heptagon (7-sided).
Step 15
Unfold all the squash folds you made in Steps 11, 12, 13, and 14. However, before unfolding, press firmly on all creases in those sections. It is crucial to leave firm folds, as these creases will be used during assembly. Once unfolded, the model returns to its pentagonal shape.
Part 2: Assembling the Pieces
Step 1
Position the pentagonal Unit—which has a total of 4 flaps (two on the right, two on the left) and three points facing away from you—so the open ends are nearest you.
Step 2
Insert your fingers into the slit running vertically through the center of this pentagon and gently spread the top layers to the right and left. You should find a triangular pocket with its open side towards you. The triangular point of the 2nd Unit will be inserted into this pocket.
Step 3
Focus on the 2nd Unit. Lift the upper flaps of the 2nd Unit from the right and left sides and bring them together in the center. While squeezing these flaps between your right thumb and index finger, you should have a triangular point with its tip facing away from you, touching the table.
Step 4
While still squeezing the flaps of the 2nd Unit with one hand, use your other hand to pry open the pocket of the 1st Unit and insert the triangular point of the 2nd Unit into it. The upper layers of the 1st Unit (on the right and left) should cover the right and left flaps of the 2nd Unit. As the triangular tab begins to enter the pocket, spread the layers and allow them to "swallow" the flaps of the 2nd Unit.
The sequence is crucial here: First, let a tiny portion of the triangle's tip enter the pocket. Then, ensure the layers of the 1st Unit cover the flaps of the 2nd Unit. Finally, push the 2nd Unit all the way inside the pocket of the 1st Unit. Meanwhile, keep the upper flaps of the 1st Unit squeezed in your hand.
Step 5
Release the flaps you were squeezing. Once the 2nd Unit is fully inside the 1st, you will see three flaps on the right and three on the left. You will also notice three triangles facing away from you. The bottom triangle (touching the table) and the one immediately above it belong to the 1st Unit. The triangle with one surface facing the ceiling—which is thicker than the others—also belongs to the 1st Unit, but it hides the tab of the 2nd Unit inside. This is why it is thicker. Note: If it makes the insertion easier, you can rotate the model 90 degrees so the tips of the triangles point left instead of forward.
Step 6
Gently spread the upper layers of the 2nd Unit from the center slit.
Step 7
Squeeze the two upper flaps of the 3rd Unit together and insert its table-touching triangle into the pocket of the 2nd Unit. You now have 4 flaps on the right and 4 on the left. The flap count increases by one with each Unit added. Repeat these steps for the remaining 9 Units. Note: You can count the flaps after each insertion to be sure.
Step 8
When the placement process of all Units is complete, you will find that the Units overlap as if they are stacked on top of each other. Once all Units are nested within one another, there should be 13 flaps on the right side and 13 flaps on the left. Unit 1 will be touching the table, while Unit 12 will be the top-most Unit you added last. To avoid confusing Unit 1 with Unit 12, attach a paperclip or place a marker on the right or left flap of the 12th Unit.
Step 9
Place your 12-unit model with the open ends on the table and the closed ends facing the ceiling. If you count the pointed triangles facing the ceiling, you will find there are 14. The triangle of the 1st Unit (furthest from you) and the triangle of the 12th Unit (closest to you) are thinner than the others. Now, we are going to perform "inside reverse folds" on the right and left flaps. Lay the model down on its left side so the cluster of flaps on the right faces the ceiling. The pointed triangles that were just facing upward are now pointing left. Unit 12, with the paper clip, should still be nearest you.
Step 10
The flap furthest from you and facing away is the 1st flap. When you touch the 2nd flap next to it, you will notice it is thicker than the 1st and consists of two layers. Ensure you are holding both layers and that their edges are aligned. You may feel small, slanted lines on both surfaces of this flap. Both lines start from the hinge (currently facing the ceiling) and extend like a "V" on both surfaces.
Now, to perform an "inside reverse fold," do the following: insert your finger into the hollow underside of the flap, ensuring you hold both layers. Then, press down on the hinge with your finger, making those slanted lines become "peaks" (mountain folds). By collapsing the hinge inward this way, the slanted lines become the new hinges. Thus, the flap tip, which was a single piece, now has two points.
Step 11
Continue this process up to the 11th Unit. As you proceed, ensure that the edges of the layers on the flaps align perfectly. Also, make sure you feel both layers before performing the collapsing/tucking process. Do not perform any operation on the single-layer flap of the 12th Unit closest to you (the marked one). Apply the same process you did in Step 10 to the flaps on the left side as well. After all the reverse folds have been completed, only the outermost flaps of Units 1 and 12 will still be "unfolded."
Step 12
Next, turn the model sideways and position it so that the 12th Unit is on your right and the 1st Unit is on your left. The "inside reverse folds" applied to the flaps in Steps 10 and 11 should be facing upward (toward the ceiling). These folds can be compared to the letter "Y." When counting from left to right, you will find that there are 11 of these "reverse fold" creases that resemble the print letter "Y."
Let's consider the Y-shape on the far left as the 1st one. Focus on the area between the right fork of the 1st "Y" and the left fork of the 2nd "Y." Hold the left fork of the 2nd "Y" with your right hand, and the right fork of the 1st "Y" with your left hand. Grip them between your thumbs and index fingers. Without releasing your grip, slide both hands toward each other until your fingers meet. At this point, your thumbs and index fingers should feel horizontal creases on both surfaces. While holding the layers this way, fold them toward yourself along that horizontal line. By doing this, the right fork of the 1st "Y" and the left fork of the 2nd "Y" disappear and become the short edges of that folded-down piece. The long edge of the piece folded toward you faces the table, while its hinge faces upward. While performing this fold, be careful not to distort the hinges that form the forks of the Y-shapes.
Step 13
Hold the right fork of the 2nd "Y" and the left fork of the 3rd "Y," then repeat the process from Step 12. Thus, the forks of the 2nd "Y" will disappear and flatten against both surfaces of their respective flap.
Step 14
Continue this step moving toward the right. Finally, after folding the right fork of the 10th "Y" and the left fork of the 11th "Y," your model will have curved into a crescent shape. Without lifting it from the table, rotate the model and repeat the same process for the 11 Y-shaped clusters on the other side.
Step 15
Take the model and hold it with one hand on the surface of the 12th Unit and the other on the surface of the 1st Unit, and squeeze. When you release the shape, it should spring back like a coil. Since the locking steps have been performed, it will not fall apart.
Step 16
We will now connect the ends of the model. Hold the model sideways and open it so the flat surfaces of the 1st and 12th Units both face the ceiling. Position it with the 1st Unit on the right. The triangular tab of the 1st Unit will enter the pocket of the 12th Unit. To do this, pry open the pocket of the 12th Unit with one hand and insert the tip of the 1st Unit's tab with the other. Once the tab is partially in, open the flaps of the 12th Unit. Ensure the flaps of the 1st Unit go under the flaps of the 12th Unit. Once the flaps are tucked in, push the tab all the way in. The model will now form a ring. Note: This nesting process is the same as the previous steps, but it may be a bit difficult. Try a few times to ensure the flaps have "swallowed" the other Unit's flaps completely.
Step 17
Apply the "inside reverse folds" from Step 10 to the remaining flaps (the joint where Unit 1 and 12 meet). Ensure you are holding two layers and collapsing them inward simultaneously.
Step 18
Apply the process from Step 12 (used on the Y-forks) to the remaining sections. The model is complete once all inside reverse folds and Y-forks are folded. You can rotate the model by holding the flaps with both hands. With each rotation, you will encounter a different surface. This model has a total of 3 surfaces.
This text is copyright 2026 by accessorigami.com and the author.
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