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