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