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