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