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