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