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