1-8
: 1s set & cast 1 place, cross LH & dance RSh round 1st corner to end 1M
  between 3s facing up & 1L between 2s facing down
9-16
: All Adv+Ret (up/down), 1s cross passing LSh & dance RSh round 2nd corner
  to end 2nd place opp sides
17-24
: 1s dance RH across (1M with 2s. 1L with 3s), 1s turn RH to own sides