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