Humility and learning
To speak a language you have to have a shift in your consciousness from your native language to your target language. This takes a lot of humility. If you are a prideful person you will not be able to do it. Why? Because you are so smart in your native language and to speak in your target language you will be very limited in your expression and make a lot of mistakes and even might sound stupid. This is a main problem with adults. They are shackled by the bonds of excess pride. You need to be humble and say I am no better than anyone else and I will sound very silly for a long while in this language. You need to let go of your native language consciousness and make a full shift. Not a half, sometimes shifts.
Even if you think and speak and think wrong it does not matter. I teach English and do not think in perfect “Cambridge-King’s English” So what. It is really about being strong enough to be humble and try to replace your native language stream of consciousness with your target language stream of consciousness.