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