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