Only possible during a Dance Battle.
Any song on easy (I chose Sandstorm)
Once the Free-4-All starts, 4 columns with moves will appear, simply perform as many of the moves as you can.
Remember you can perform a move in any column so target the gold ones first as they are worth 40,000 points (a normal move is only worth 10,000).
As an opponent can steal moves by perfoming them first have your friend stand still.