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