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