1. The best place to learn a language is to be in the place where the language being is spoken. Many years back I was given this advice about learning a new language, it states "to learn the language of the land you have to drink from the water of the land" This is incomparable to those online classes. If you want to speak French go to France.
2. Totally forget about the structure, semantics and phonetics of the language. Just receive the language as heard, speak as heard, take it as a song. Don't start doing the linguistics of the language before mastering the language, you will end up not learning both.
3. Take every language as a sound. Boo, Bah, No, Hoo. Let's take a study on babies, a baby start speaking with sounds, the baby does not care about twenty six alphabet, five vowels and twenty one consonants in English language. They just make the sounds, then alphabets to alphabets, morphemes to morphemes the baby speaks the mothers language unconsciously. You are like a baby to every new language, sorry.
4. Be intentional about the language, s'il vous plaît. Many people tend to take classes on a foreign language and the only time they get to use the language is when their language class is up. You will not learn that way. Go and download movies on the language, don't add subtitles at first then try to explain the movie to yourself, you may later add subtitles for your rating. Do this for songs and books as well.
5. Speak the language anywhere anyhow. (This is if you are in the land where the language is being spoken.) Don't get to a shop and tell them mon français la ce empê empê, ce ne pas tros bonne. (My French is small small, it is not that good) speak the language for them like that, let them laugh they will correct you. Don't be distracted you know what you want, the shame is not worth it.
6. The level of your adaptability is proportional to how fast you will learn a new language. How fast do you adjust to new things? Do you get pissed when something new is introduced to you? Can you camelionize yourself?
7. The level of your intelligence determines how fast and how well you will learn the language. We all know that intelligent people tend to learn quickly and easily, so no much talk on this.
8. If you love music or you are a Choir person the chances of you learning and mastering a foreign language quickly and easily are higher. Music will help you.
9. Teach the little you know. They said, if you never want to forget a thing then you teach it. Teach the little rubbish you know about the language, teach your friends and families they will not pay but you just keep teaching.
10. Love the language. I made this point last because I want you to remember it. Your love for the language is an advantage for you. It will make you go that extra mile and carve out time from that your busy schedule. Some people will say love is a language, well I don't know what it means and I don't know if it concerns this article.