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