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