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