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