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