My idea is like this.

1. In the very beginning, you'll have to get a good grammar and phrase book or website and learn the most basic words and phrases by brute force.  You spend a month or two this way to get your vocabulary up to the minimum required level.

2. Find good dictionaries, both a serious one as well as a browser-based pop-up dictionary so you can look things up quickly.  Get good texts and try to read them.  Find them in subjects you like, like children's tales and allegories, preferrably something you're familiar with.  Also find matching English versions of the texts.  Then you plow through the texts, looking up new words and grammar as they come along.  Get the matching audio books as well and listen, if they're available.

3. Continue reading broadly, increasing the level of difficulty gradually.  Expand listening to radio and TV news casts. Mix in watching language videos, practice conversations as you like, but also keep reading and listening no matter what.  Do it until you can comfortably read newspapers, novels, current affair magazines, and so on.

Personally I think this reading and listening-based learning is the best way, especially if you are a type who loves reading. But it is not for everyone obvisously, as some people just can't read very well.  No matter which route you take, reading and listening are the most important activites for expanding your vocabulary, so don't neglect it.

If you know enough french to understand simple phrases, I suggest you learn the lyrics of a couple of french songs and sing along. You will get used to the pronounciation and you will learn a few words in the process. 

Keep practicing with native speakers, but try to learn some new grammar and vocabulary between each exchange. Repeating the same basics over and over may bore you, discourage you and keep your language skills low. 

To define your own goals might be effective.SVP.

I think the best way is to paractice by conversation