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