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