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