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