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