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