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