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