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