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