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