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