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