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