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