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