Pressing jump during the recovery of an attack will cancel it with a jump.
Swapping weapons/shields right before an attack lands will cancel all recovery.
This method is slightly faster than the Jump version and since the swap freezes the game it allows extra hits on a stunned boss.
Swapping shields right after a Parry will cancel the slow-motion animation and allow extra hits during a stun round. This technique also make parries safer, since it cancels the vulnerable state after a failed parry with a blocking state.