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