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