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