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