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