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