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