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