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