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