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