One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,4)(5,6,10,16,11,15,32,42)(7,17,20,43,21,12,30,35)(8,22,25,44,26,13,31,38)(9,27,28,56,29,14,39,41)(18,33,23,36,48,45,51,52)(19,34,49,61,50,46,57,66)(24,40,54,65,55,37,58,63)(47,59,53,62,67,60,68,64)(5,7,11,21)(6,12,15,17)(8,23,26,51)(9,19,29,50)(10,30,32,20)(13,36,22,52)(14,34,27,46)(16,43,42,35)(18,31,48,25)(24,53,55,68)(28,57,39,49)(33,44,45,38)(37,62,40,64)(41,66,56,61)(47,58,67,54)(59,65,60,63)(2,4)(5,8)(6,13)(7,18)(9,24)(10,31)(11,26)(12,33)(14,40)(15,22)(16,44)(17,45)(19,47)(20,51)(21,48)(23,30)(25,32)(27,37)(28,58)(29,55)(34,60)(35,52)(36,43)(38,42)(39,54)(41,63)(46,59)(49,68)(50,67)(53,57)(56,65)(61,62)(64,66) involution — undirected(5,9,11,29)(6,14)(7,19,21,50)(8,24,26,55)(10,28,32,39)(12,34)(13,37)(15,27)(16,41)(17,46)(18,47,48,67)(20,49,30,57)(22,40)(23,53,51,68)(25,54,31,58)(33,59)(35,61)(36,62)(38,63)(42,56)(43,66)(44,65)(45,60)(52,64)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.