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