Fold a waterbomb base , colored side out. Unfold to the original square. Turn over, so the white side is up. Fold up a strip along the bottom. Mountain fold , and turn over.
Valley fold a strip to match the rear as closely as possible.
Undo the mountain fold. Fold in the sides, to match the top and bottom as closely as possible. Blintz fold through all layers. Rotate 45 degrees, and turn over. Fold the bottom edge nearly, but not quite, to the centerline.