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