1-8
: 1s followed by 2s+3s lead down middle; 2s+3s divide & 1s+2s+3s lead up
  remaining in middle
9-16
: 1s+2s+3s promenade
17-24
: 1s cross RH, cast (2s step up); 1s cross RH, cast (3s step up)
25-32
: 2s+3s+1s circle 6H round & back