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