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