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