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