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