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