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