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