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