I am not sure of what you are looking for exactly. If you mean what to do to lead into these spins, I suggest a sidekick or roundhouse into the spin. If you mean what to practice on: a kick paddle is the best to develop your aim and once you can land that without error, try a board. A single board should be easy since you are hitting it with your heal with either kick. Although if the person holding the board is a limp noodle that will ruin any break.