One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,4,6)(3,7,8,5)(25,26,29,34,31,36,30,35)(27,37,41,32,39,48,40,47)(28,42,44,50,45,49,43,33)(38,52,54,56,53,46,55,51)(1,3,4,8)(2,5,6,7)(9,10)(11,15)(12,16)(13,14)(17,23)(18,21)(19,24)(20,22)(25,27,31,39)(26,32,36,47)(28,38,45,53)(29,40,30,41)(33,46,50,52)(34,37,35,48)(42,56,49,51)(43,54,44,55)(10,14)(15,21)(16,22)(23,24)(25,28,31,45)(26,33,36,50)(27,38,39,53)(29,43,30,44)(32,46,47,52)(34,49,35,42)(37,51,48,56)(40,54,41,55)(9,11,13,18)(10,15,14,21)(12,19,20,17)(16,24,22,23)(27,39)(32,47)(37,48)(38,53)(40,41)(46,52)(51,56)(54,55)(9,12,13,20)(10,16,14,22)(11,17,18,19)(15,23,21,24)(25,29,31,30)(26,34,36,35)(27,40,39,41)(28,43,45,44)(32,37,47,48)(33,49,50,42)(38,54,53,55)(46,51,52,56)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.