Level 4-7 is easy. Just cut the rope, pop the bubble and let the candy go in and out of the magic hats. You don't have to use the air puffers like the other solutions. This doesn't work every time because sometimes after about 15 seconds the candy just falls. It probably depends on the height in which you pop the bubble to have to right momentum, but i got it on my 3rd try going for the magician achievement.