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