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