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