A lot of 1960s watches had very unique styling. There are some plain Janes, of course but in may situations you can spot a 1960's model just by it's appearance. They will often have florentine engraving, unique lugs, unusual hands, and especially calendar complications.
A good example is the 1966 Dateline T-482. It has curved lugs, an engraved bezel, and a simple dial with a mismatched hands.