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