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