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