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