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