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