Quote from jimmyx
I read the Mx0 raws and they were pretty easy to read. Most manga have furigana so having lots of kanji would help with your reading skills.
Kurohime is a pretty easy to read manga as well.
"most" is an incorrect statement. Basically just shounen/shoujo stuff. It does help though, just be sure to pick something [like mx0] with very basic speech if you're a beginner.
As for actual methods of practice, if you know a little watching raw dramas/movies (or even some anime with more realistic settings) will help you a lot as you gradually associate words with actions that way. For preparation it might be best just to go along with the JLPT since you'll probably want to get a certification if you're going to use Japanese professionally rather than just as a hobby or whatever.
Living in Japan does help a lot, but only if you actively speak Japanese. I know people that just wander around aimlessly and expect increasing their volume to get them whatever it is they want. It does work sometimes, but about 90% of the time I immediately feel like slapping them.
On a more technical note, make an effort to learn casual speech. Most of the textbooks I've seen only teach more formal forms, and those aren't as useful unless you're in a business setting.
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