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