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