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