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