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