How do I set up the barre attachment?

Easy peasy - positioned against the back wall of your FLOW box are 2 Barre paddles and a ballet bar (that is separated into 2 pieces). Remove these items, slide the narrow end of the paddles into the slot provided at the end of the your box. Screw the two pieces of the bar together and then slide the metal ends of the bar into the cut-out on the top of the barre paddles.