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