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