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