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