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