We started off sitting on the step that was part of the stage facing opposite directions (diagonals) kind of thinking to ourselves with the "at wanamakers and saks and kleins..." etc bit and then I (Adelaide) stood up on the note before "why not?" and she stood up on the note before "why not what?". Does that make sense? It looked really good.
We had various other little bits and pieces that worked well - another good one was on "save the fist..." she went to punch my face and I ducked down simultaneously. It's really weird writing this stuff out, it did look good! Good luck