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