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