Origami Cube (Water Bomb)

This requires a square of paper.

Cube Base

From the reverse side, fold and unfold the diagonals.

From the obverse side, fold and unfold the mid-lines.

Push in opposite sides and fold back the top to collapse the square into a triangle.

Cube (continued)

Fold up the 2 bottom corners on both faces.

Fold in the 2 side corners on both faces.

Thin Paper Variation

Double fold the 2 top flaps into the pockets on both faces.

Crease top and bottom corners to prepare cube edges.
Blow into the hole in the bottom to inflate the cube.

Thick Paper Variation

Fold the 2 top flaps into the pockets on both faces.

Crease top and bottom corners to prepare cube edges.
Blow into the hole in the bottom to inflate the cube.