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