Actually, she was showing Hughes were the step was behind the podium. Sarah came to the front instead of the back to give the other competitors a hug, and then looked down like "How am I going to get up there without falling?" Michelle pointed back to the step, but Hughes just stepped onto Kwan's spot and then up onto hers (which I thought was a little tacky...but who cares:)
The judges are deciding the rest of her life and she is joking to the camera...priceless, and just like a regular teenager who goes to school.