For me one of the most difficult things with French is to remember my masculine and feminine nouns. If you make the wrong choice, all the accords, the associated past participles and adjectives will be incorrect and the whole phrase will fall flat like a line of dominoes. There is some general advice as to the likely to indicate masculine and feminine nouns, but that can only take you so far.
The method I have been trying out is a sort of memory-association technique. When I was about 16 I saw a French film called L’Enfer which starred the French film actress Emmanuelle Béart. In the film she is the subject of the all-consuming jealousy of the male protagonist and for me came to embody French feminine allure.
You might equally choose Sophie Marceau or Jeanne Moreau, Catherine Deneuve, Béatrice Dalle or Audrey Tatou. However, when I think of feminine words it will be her image that comes to mind. So if I appear to be getting a bit steamed up when I reel a seemingly banal phrase, you will know why.
In terms of masculine nouns, obvious figures might be GérardDepardieu, Eric Cantona, Sébastien Chabal, Jacques Chirac, Bernard Hinault or even Charles de Gaulle. I went for Bernard Tapie, a larger than life personality, an entrepreneur-champagne socialist who combines characteristics of aggression, super confidence, risk-taking, relentless energy, playfulness and a tremendous will.
This method is, of course, just a tool to assist the process of memorizing masculine and feminine nouns. It does not mean you are being in any way sexist. After all, we all know that they are a great many aggressive women as well!
Try it and let me know how it goes!