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