Starlight Princess is a hot tumble slot: winning symbols drop away, new ones fall in, and a multiplier orb can raise that cascade. There is no payline to count. You set a stake, press spin, and stop when the credit limit you wrote down is gone.
The short answer is simple. Start in Starlight Princess Demo on the lowest stake, watch how often an orb lands during a tumble, and only then open a live round. Two buttons below reach the same room.