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