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