When I moved here, I was 17 and just out of highschool. I'd taken one year of French in seventh grade, and knew about three words:
(hello, shit, and fall down)
It wasn't enough. Taxi drivers and French waiters took advantage of me, and I would walk down the streets in my bubble, not understanding when people spoke to me (unless it included hello, shit, or fall down...) and since the dogs in France are free to poop wherever they like and 'merde' is also used as 'Good Luck' I heard that word a lot.
The first words I learned were 'Right, left, and straight ahead'. I had a map, addresses, and I had to go from one end of Paris to the other every day on my endless round of 'Go-Sees' which is what a model does - go see the clients, the photographers, the art directors. So off I went, map in hand, and a vague notion of 'right, left, and straight ahead'.
Luckily the metro system in Paris is idiot-proof. It is Really easy to use. And it goes all over the city. I got to where I had to go with no trouble. (not too much trouble)
My big break came when I started dating a Frenchman. His English was limited, but his cousin had studied in England, and she came on most of our dates and translated. Learning the language of love while in love is perfect - and having a private tutor is even better. Things that helped the most:
Reading comic books (the French Love their comic books, and every house has a pile of 'Asterix', 'Tin-Tin', and 'Gaston LaGaffe'. )
Playing scrabble. (dictionary in hand, I beat the old ladies in the scrabble club. They let me cheat and use the dictionary. They served me tea and little lemon biscuits, and corrected my terrible grammar. Joining a scrabble club, reading comics, and dating a French man made learning French a lot of fun.
(they should think about that in school...)