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