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