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