One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,6)(4,5)(7,8)(9,10)(11,13)(12,14)(15,16)(19,26)(20,21)(23,31)(24,30)(27,32)(28,29) involution — undirected(2,5)(6,8)(9,11)(10,13)(12,15)(14,16)(17,18,22,25)(19,27,29,23)(20,30,21,24)(26,32,28,31)(11,15)(13,16)(17,19,22,29)(18,23,25,27)(20,26,21,28)(24,32,30,31)(11,15)(13,16)(17,18)(19,23)(20,30)(21,24)(22,25)(26,31)(27,29)(28,32) involution — undirected(1,3,4,7)(2,6,5,8)(10,14)(13,16)(17,20,22,21)(18,24,25,30)(19,28,29,26)(23,31,27,32)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.