From an tidal wave (a wave longer than 4 dancers):

Everyone who can Trades (turns 180 degrees) with the right hand, then
everyone who can Trades (turns 180 degrees) with the left hand.

If the call is "Grand Left Swing Through", the action is left turn, then right.

To see Grand Swing Thru in more situations, click here:

Note: TAMINATIONS will open in a new window.