Immersion. From everything I've seen/read/heard, immersion is quintessential to learning not just Japanese, but anything, really. If you think about it, it's how you learned English in the first place - assuming, of course, that it's your first language. Or, perhaps it isn't; in which case you would still need to learn via immersion if you really want to get good at it.
Let's back up a few paces and glance at what immersion is from afar. Immersion is basically surrounding yourself with what (language, in this case) you are trying to learn. Full immersion is completely cutting all ties (within reason, of course) to your primary language and converting/changing all those things around you to be in the language you are striving to learn. This includes a lot more than you might consider at first.
Obviously one cannot start at full immersion. Completely changing everything all at once will take your productivity down to zero. So, pace yourself. Change one thing a day, no matter how small or insignificant it may seem. Or, convert once thing at a time, only moving to the next thing once you're comfortable with what you've already converted. There's no rush.
I have broken down Immersion progress into 4 phases, as follows:
- Beginnings - This is where you start. This means that a few things are converted to Japanese, but nothing that imposes greatly on your daily schedule. Stay here for the first few weeks to get comfortable with it. At this point, maybe you've started purchasing some Japanese music, or have begun trying Japanese food. Watching anime (in Japanese, of course) counts as well.
- The Halfway Point - At this phase, about 30-50% of everything you do should be in Japanese. This is when you begin discarding items from your primary language in favor of equivalents in your target language (Japanese). Some important things in your life should be converted, but nothing that would be a show-stopper if you don't understand it. It's okay to revert back to English when needed at this point. Before proceeding to the next phase, you should know the Kanji (meaning and writing) and Kana scripts.
- Almost There - To reach this phase, you'll need to be able to know at least the Kanji and Kana, as well as some readings. This is the point where you toss the majority of things in your primary language in favor of Japanese. Install that Japanese operating system. Convert your online accounts to Japanese, and only view Japanese websites. Same goes for music and reading. At this point, if you don't know something in Japanese, you should be able to look it up in Japanese to find your answer. Readings are a must to move on from this phase.
- Home Stretch / Full Immersion - To reach this point, you shouldn't ever have to refer to your primary language for anything. You should be able to accomplish anything in Japanese, or at least find out how to by using Japanese. This is the phase that will take you to fluency.
Here's a list of what I have converted to Japanese:
- Radio/Music - even though I don't understand 90% of it yet, I am already beginning to understand how it sounds on a high level. Occasionally I'll pick up a word or partial sentence. I no longer listen to this in English.
- Home Computer - Downloaded a Japanese language pack and created a separate user set to Japanese. This way, if I run into a serious issue that I just don't understand, I can still swap back to English. However, that being said, my goal is to have the English user gone within about 6 months, and only use the home computer in Japanese. Aiming too high? We'll see.
- Websites- I've started going to the Japanese version of websites if they are available. I still visit English ones as well, but I am working on finding Japanese replacements for them if I can.
Converting things for work probably won't come until phase 4 (or at least phase 3) simply because I need to be proficient enough in it to function without hindering productivity.
This article may be updated as I go, at least until I reach what I consider to be phase 2.