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)(11,16)(12,14)(13,15)(17,18)(19,28)(20,25)(21,26)(22,27)(23,31)(24,29)(30,32) involution — undirected(2,5)(6,8)(9,11,13,12)(10,14,15,16)(17,19)(18,24)(20,23)(21,30)(22,29)(25,26)(27,28)(31,32)(11,12)(14,16)(17,20)(18,24)(19,23)(21,29)(22,30)(25,31)(26,32)(27,28) involution — undirected(1,3,4,7)(2,6,5,8)(9,12,13,11)(10,14,15,16)(17,20)(18,25)(19,21)(22,30)(23,29)(24,31)(26,28)(27,32)(11,12)(14,16)(17,21,22,23)(18,26,27,31)(19,20,29,30)(24,32,28,25)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.