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