One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,6)(4,5)(7,8)(9,10)(11,14)(12,13)(15,16) involution — undirected(2,5)(3,7)(17,18,22,26)(19,27,29,41)(20,32,34,46)(21,35,28,25)(23,36,37,31)(24,39,40,33)(30,44,43,38)(42,47,48,45)(10,13)(14,16)(17,19,28,36,22,29,21,31)(18,23,35,41,26,37,25,27)(20,30,39,47,34,43,33,45)(24,38,46,48,40,44,32,42)(2,5)(6,8)(9,11,12,15)(10,14,13,16)(19,29)(23,37)(27,41)(30,43)(31,36)(38,44)(42,48)(45,47)(1,3,4,7)(2,6,5,8)(17,20,28,39,22,34,21,33)(18,24,35,46,26,40,25,32)(19,30,36,47,29,43,31,45)(23,38,41,48,37,44,27,42)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.