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