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)(11,14)(12,16)(13,15)(17,18)(19,28)(20,24)(21,25)(22,27)(23,29)(26,30)(31,32) involution — undirected(9,11,14,10)(12,16,13,15)(17,19)(18,23)(20,22)(21,29)(24,32)(25,28)(26,27)(30,31)(2,5)(6,8)(9,12,14,13)(10,15,11,16)(17,20,31,29,21,30,22,19)(18,24,32,23,25,26,27,28)(1,3,4,7)(2,6,5,8)(9,12,14,13)(10,15,11,16)(18,25)(23,28)(24,26)(27,32)(9,13,14,12)(10,15,11,16)(17,20,22,19,21,30,31,29)(18,26,27,23,25,24,32,28)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.