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)(11,14)(12,13)(15,16)(17,18,20,23)(19,25,28,22)(21,24,30,31)(26,27,32,29)(2,5)(6,8)(17,19)(18,22)(20,28)(21,27)(23,25)(24,26)(29,30)(31,32) involution — undirected(1,3,4,7)(2,6,5,8)(10,13)(14,16)(17,18)(19,26)(20,23)(21,31)(22,27)(24,30)(25,29)(28,32)(19,27)(21,30)(22,26)(24,31)(25,32)(28,29) involution — undirected(9,11,12,15)(10,14,13,16)(18,23)(22,25)(24,31)(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.