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