Thoughts:
-- Ask your instructor to teach the dip from scratch to another woman while you observe.
-- Do the dip holding on to a bar, perhaps with a helper for holding, beginning with the amount of dip that you're comfortable with, and through successive approximations, dip increasing amounts as you're comfortable in doing so.
-- Mentally prepare and desensitize yourself for the show dip by imagining yourself doing it fully, successfully, and to dramatic effect.
Best wishes, and let us all know how things went (I trust spectacularly well).