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