Go at a decent speed so your comfortable with it. Setup like and Inward Heelflip then pop down. When you pop you should start to turn your B/S Heelflip. Just think of it as a regular B/S 180 but you add a Heelflip with it. Try to stay overtop of the board don't be afraid to land on it. It is better to first do a B/S 180 with half a Heelflip then actually try to land the full thing. When your dragging your foot try not to get caught while the board is spinning. Tuck up a lot and you should be fine.

Good luck!

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