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