A personal rather than comprehensive or properly representative selection- which would include A Bout de Souffle, Jules et Jim, Cleo from 9 to 5, Out 1, The Umbrellas of Cherbourg, Le Boucher, La Jetée..
Taking the period from the late 50s up to 1974, excluding later films by New Wave directors, like Sans Soleil and my beloved The Green Ray, though maybe I should include them since cut-off points seem arbitrary.
Giving myself plenty of leeway, I'm including the peripheral Malle, Pialat, Robbe-Grillet and also Melville for his direct influence on the NW. Even a central NW figure, Rohmer, was making films before it supposedly began, ditto Marker and Resnais on the "left bank". I'm not including Bresson or Tati.
My own favourite NW directors are Rohmer and Rivette. Oh and it's well worth getting to know other national "New Waves" centred on the 60s, the Japanese and Czechoslovakian for instance.