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