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