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