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