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