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