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