In the options set the match count to 2 or higher. Win 30 interrupted (ie when a second player jumps in) matches in Arcade or Random mode with Honey. At the start of the 31st match do the armor break technique and win the round. At the start of the second round, Honey's skirt will be gone. This can be done numerous times after the 31st match provided you don't lose.
Note: this trick cannot be saved to the VMU and must be done over again if the DC is turned off.
In Arcade Mode, get to and defeat Mahler in under 5m50s with at least half your strength or with a Super K.O. (or Armor Removal), then defeat Kuhn in the Bonus Stage.