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