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