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