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