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