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