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