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