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