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