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