Use it often as you can and also have someone to speak it with

Immersion. Use it everyday in your regular life.

submerse yourself in that language - daily practice it and reduce the use of your normal language...in a couple months you will sound intermediate maybe

Immerse yourself in it, change the language settings on your phone, and TV.

Steal a person's brain that has a different language in it and then eat it.

Move into a little village by yourself. I learned very quickly that way.

Getting a concussion and forgetting all language. Then traveling to wanted country, using cocaine and trying to talk to locals every day until you are fluent.

being around people who speak the language. put yourself in a situation where you have to learn a language. maybe you can look up penpals online that can help you with a particular language

Move to the country where they speak it.

Go to the country where its spoken

IMMERSION

PRACTICE
READ
LISTEN TO MUSIC
CONVERSE
MEMORIZE IN VISUAL WAY WORDS AND GRAMMAR RULES

Rosetta Stone.

Move to the country of the languages origin.

Drop your native language