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