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