i cannot do an S-bend, but these are things i hear.
edge in like a raley, once you leave the wake, look into your back armpit to initiate the rotation. let yourself do the 360. be carefull not to pull on the handle until you are back to facing the water like a normal raley, THEN pull the handle down. someone also told me you can kick your back foot around... i duno if it works or not.
as far as a vulcan, i believe thats an S-bend with a rewind 180? i would think that would be a handle push away but i duno.