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