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