Play on Easy. Once you have the feather and begin the 2nd act, look for a beehive thing that spits out the flying enemies either in Bauer's Reach or Mouldwood Depths. There will usually be 4 or 5 on screen at once. Jump up and hold RT while you bash off of them and jump around (bash resets your double dump), swinging your spirit blade in between bashes and jumps. Triple Jump (or even Launch near the end of the game) will make it easier, but this one is cake on Easy difficulty.