One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,6)(4,5)(7,8)(11,15)(14,16)(18,20)(19,25)(22,29)(23,31)(26,32)(27,30) involution — undirected(2,5)(6,8)(9,10)(11,14)(12,13)(15,16)(17,18,21,20)(19,26,27,23)(22,24,29,28)(25,31,30,32)(10,13)(14,16)(17,19)(18,23)(20,26)(21,27)(22,30)(24,31)(25,29)(28,32) involution — undirected(9,11,12,15)(10,14,13,16)(17,20,21,18)(19,26,27,23)(22,28,29,24)(25,31,30,32)(1,3,4,7)(2,6,5,8)(18,20)(23,26)(24,28)(31,32)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.