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