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