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