The three dominant Gods in Ustalav are Pharasma, Urgathoa, and Desna.  Among their symbols are spirals, skulls, and butterflies, respectively.

What’s the most important factor is choosing your deity?  The kind of cape you get to wear, obviously.  Here are some choices for discerning worshipers of the three gods.

(Valentino Spring 2013 Couture; Manon Kündig, Antwerp Fashion Department Show, 2011; Valentino Fall 2014, Ready-to-Wear.)

The Manon Kündig piece inflates to actually be skull shaped, there’s an inflated pic in the show’s gallery.