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