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