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