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