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