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