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