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