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