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