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