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