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