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