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