[MartinHarper]

In Ceroc, I tend to use a comparatively more hooky grip for the catapult lead, palm upwards, to better distinguish it from a windmill, for which I tend to use a flatter palm-to-palm grip. Since the windmill and catapult are traditionally easily confused, I hope this helps.

In Jazz Jive, I lead it starting left to right, signal by bringing my right hand over onto the top of the lady's hand, then transfer hands, and pushing the lady's hand behind me. Incidentally, the Jazz Jive lead appears to work on Ceroc ladies, and vica versa.