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