Cut the one open side of the paper folded in the shape of a triangle at equal intervals with scissors. Cut from the outside to the inside, leaving a small crease in the middle.
Unfold the paper.
Apply glue to the center fold.
Glue the cut end of the paper to the center.
Leave the tail part.
Glue the other side, too.
Make a small cut in the middle of the top corner and fold both sides outward to form the mouth.