The video shows a person decorating a cupcake with green frosting. The person is using a piping bag to apply the frosting in a circular motion, creating a pattern on top of the cupcake. The cupcake is placed on a white surface, and the person's hand is visible as they hold the cupcake steady while decorating it. The frosting is bright green in color, and the piping bag has a round tip that allows for precise decoration. The person's movements are steady and controlled, indicating that they are experienced in cupcake decorating.