I got started with English from playing the Sierra adventures (Police Quest, Space Quest) with a dictionary. But what really got me going was when I started reading English books. That got me a rich vocabulary and an understanding of the grammar. The second big leap for me was when I worked for a Space Agency and spoke nothing but English all day. The native English speakers told me that my English is much better than theirs. The reason was that I learned 'proper' English while they sometimes used the dialect they grew up with.

People I know raise their kids perfectly bi-lingual (Dutch French) from the cradle. One parent speaks French, the other Dutch. The kids learn it naturally and it gives them a huge advantage in life.

We taught our daughters basic sign language from the moment they were able to wave their hands. That was a real joy. They were never frustrated due to communication problems, because from 6or 7 months they could tell us whether they were thirsty, hungry, tired, ... And since we always used the words with the signs, they started talking coherently at a very young age, especially my oldest daughter. She could speak in perfectly pronounced full sentences by the time she turned 2. This always got some funny reactions from people who didn't expect that.