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