Lay a sheet of patterned origami paper pattern-side up. Fold the paper in half on the diagonal, bottom corner to top corner (1). Fold the triangle in half, right corner to left corner (2). Open the top half of the triangle (3).

Flatten it into a diamond (4). Flip the paper over, and fold the "fin" to the left (5). Open the fin, and flatten it into a diamond (6).

Fold the top-right and the top-left edges to the center line (7). Open the flaps, as shown (8), and flatten the bottom of each into a triangle (9).

Flip the paper over (10), and repeat steps 7, 8, and 9 (11). Rotate the flaps: Fold the top-left flap to the right. Flip the paper over, and repeat (12).

Fold the top-right and top-left edges to the center line (13). Open the flaps, as shown, and flatten the bottom of each into a triangle (14). Flip the paper over, and repeat (15).

Fold the top point down, as shown. Flip the paper over, and repeat (16). For the flaps: Fold the top-left flap to the right. Flip the paper over, and repeat (17). Fold the top point down, as shown. Flip the paper over, and repeat (18).

Pull out the four points (19). Flatten the bottom of the box (20).