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