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