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