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