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