English in 6 Months
I'm a spanish native speaker, so the foreign language I learned was english. I learned by myself so maybe my level is not perfect, however I can say that I got better results than studying in a bilingual school.
The reason? Well... First, I had some free time. That's very important cause learning a language requires getting used to the rhythm of the words, the gramatic structure, the sounds themselves, and the usual 1-2 hours that most people allocate for their studies, are simply not enough. I would say 5 or more hours is a good start.
Second, I looked from good learning material. Any kid can learn some words in any language, but there are always rules to follow and exceptions to those rules which we should know and remember. The web is full of learning resources, from vocabulary to grammar. Just spend some time and review carefully the contents of the sites, since not all offer the material in an easy-to-learn format.
Third, slow but sure, I tried to read articles and books in the new language. At beginning is really difficult, since you don't know much about the vocabulary and the structures and so, but with time your brain will adjust itself and suddenly you will find yourself understanding the context of what you are reading (if not the whole content) and in few months you will start understanding the context itself. And if everything goes well... then in another 2 or 3 months you will reach a decent level of reading comprehension.
Fourth, the multimedia content. We need audio and video to get used to the day to day use of the language. Reading is good for learning grammar, but since nobody talk like they write, then we need the multimedia to learn slang and common language.
After that, is the chat. Of course, we need to start writing in the new language, and the faster we do it, the better. So the online chats are the best way to practice our recently accquired language skills. And people will correct our mistakes too. No need to be embarrased cause nobody is looking at us.
And finally, if everything went well, with the friends you made online, you can start videochat and practice your talking skills. That's what I did. Step by step. It took me 6 months from the momment I started to the level I'm using now. My pronountiation is not the best (I still need to travel to english-speaking countries) but my husband tells me is much better than most english-teachers in my country.