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