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