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