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