[DarkYak]

Duolingo for japanese and hello chinese for chinese. Also watch movies + videos with those languages.

[janleongi]

Go to the country where its spoken and force yourself to learn through interacting with others and taking their language courses

[o0835]

avoid learning off anime if you don't want to sound like a weeb, I recommend Japanese TV shows or dramas instead

[Mikezero]

Immersion if you can do it.
The All Japanese All the Time method can be applied to any language and is probably as close to immersion as you're going to get without actually going to another country.
Italki is a really good place to find language partners to practice with, or teachers - 1 on 1 lessons can be super helpful.

[Jack89725]

Watch a lot of media and listen to the langauge.

[caesar_caesar]

The best way would be speak them out, that's the way you'll know whether if your pronunciation is right