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