The child draws the ghost outline on the black card with a white chalk pencil or simply begins gluing freehand. Swipe the glue stick thickly over a rounded head shape at the top, then drag the glue downward in a narrowing wiggly curve for the body. The trail of glue is the ghost shape.
Press cotton balls into the glued area one at a time, packing them closely together so no black card shows through the main body. The edges will be naturally fluffy and uneven, which is exactly right.
Cut two small circles from black paper (or use a hole punch) and glue them onto the cotton surface for eyes. Press firmly. Leave flat for five minutes until set. The ghost is ready when the cotton balls resist a gentle tug.