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