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)(11,13)(12,14)(15,16)(17,18)(19,25)(20,26)(21,27)(22,37)(23,29)(24,30)(28,38)(31,39)(32,40)(33,41)(34,42)(35,44)(36,45)(43,47)(46,48) involution — undirected(2,5)(3,7)(9,11,12,15)(10,13,14,16)(17,19)(18,25)(20,33)(21,22)(23,38)(24,32)(26,41)(27,37)(28,29)(30,40)(31,35)(34,46)(36,47)(39,44)(42,48)(43,45)(10,14)(13,16)(17,20,21,34,24,36,23,35)(18,26,27,42,30,45,29,44)(19,31,38,47,32,46,22,33)(25,39,28,43,40,48,37,41)(2,5)(6,8)(17,21,24,23)(18,27,30,29)(19,22,32,38)(20,34,36,35)(25,37,40,28)(26,42,45,44)(31,33,46,47)(39,41,48,43)(1,3,4,7)(2,6,5,8)(17,22,21,19,24,38,23,32)(18,28,27,40,30,37,29,25)(20,33,34,31,36,47,35,46)(26,43,42,48,45,41,44,39)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.