I heard that Duolingo is not good at teaching you how to actually use a language, instead focusing on the parts that are easily measured. Because of that, I never tried it and don't know how accurate that evaluation is, but here's what helped be when learning Chinese:
- Regularly meet with a native speaker (1 hour per week for me): they can correct your mistakes and try to explain confusing aspects of the language
- Read https://en.wikipedia.org/wiki/Help:IPA/Target_Language and https://en.wikipedia.org/wiki/Target_Language#Phonology and the descriptions of individual sounds linked there. It will help you to consciously position your tongue to produce the sounds and practice until you can do it subconsciously. Doing it purely by ear is much harder. You probably won't sound like a native speaker anyway, but get much closer than someone who approximates everything using sounds from their native language.
- Watch movies in your target language (every day before going to sleep, in my case), with subtitles until you can do without. You'll almost certainly notice a few words every time which are repeated frequently. Pause the video and look them up. They might not be useful in everyday conversations (I know way too many titles of members of the Chinese imperial court), but if you stay within a genre, they'll still help improve your understanding as you keep watching.
- Use spaced repetition to review vocabulary. Turn it into a habit to add some fixed number of new words every day and then review. If you keep it up for a few years, even small increments add up to a sizable number. Fortunately, spaced repetition increases the intervals between reviews, so the time cost each day stays manageable. If you use Anki, I also recommend looking for addons to add pronunciations automatically (even robotic speech-to-text can be helpful).
- To practice reading, start with headlines from a newspaper website (even if it's just a single headline initially and you have to look up every word). Then work your way up to paragraphs, articles and eventually books.
- I never practiced writing much (except when memorizing individual Chinese characters), but if you can speak and read, you can probably write. If your target language has a different keyboard layout, figure out how to switch to it in your OS and practice typing. For Linux, I can't plug Fcitx enough, especially for its awesome Unicode input feature.
- Finally, nothing motivates more than putting yourself into a situation where you have no choice but use your language. After 2 years of studying Chinese, I somehow managed to rent an apartment in China using only my still pretty limited speaking ability and the pressure of that and similar situations has helped me improve tremendously.
I don't know any native french speakers in my area but I often thought about skyping those number on fiverr where people offer to chat with you and do exactly the same. I can also attest that watching TV serials in french was pretty entertaining (i saw whole 2 seasons of maison close) with and without subs when i was on that 300 day streak.. it really was super fun. But i think at the end of the day it all boils down to practice and repetition and most importantly if you're doing it out of need or just fun (in later case you never take it seriously like you said in your last point which was sadly my case as i really don't have any need for it).
Duolingo is horrible on mobile because you miss the lesson details with explanations. It’s really only good for basic vocabulary and heavily depends on the people putting the language tree together. In any case repetition is key.
- Regularly meet with a native speaker (1 hour per week for me): they can correct your mistakes and try to explain confusing aspects of the language
- Read https://en.wikipedia.org/wiki/Help:IPA/Target_Language and https://en.wikipedia.org/wiki/Target_Language#Phonology and the descriptions of individual sounds linked there. It will help you to consciously position your tongue to produce the sounds and practice until you can do it subconsciously. Doing it purely by ear is much harder. You probably won't sound like a native speaker anyway, but get much closer than someone who approximates everything using sounds from their native language.
- Watch movies in your target language (every day before going to sleep, in my case), with subtitles until you can do without. You'll almost certainly notice a few words every time which are repeated frequently. Pause the video and look them up. They might not be useful in everyday conversations (I know way too many titles of members of the Chinese imperial court), but if you stay within a genre, they'll still help improve your understanding as you keep watching.
- Use spaced repetition to review vocabulary. Turn it into a habit to add some fixed number of new words every day and then review. If you keep it up for a few years, even small increments add up to a sizable number. Fortunately, spaced repetition increases the intervals between reviews, so the time cost each day stays manageable. If you use Anki, I also recommend looking for addons to add pronunciations automatically (even robotic speech-to-text can be helpful).
- To practice reading, start with headlines from a newspaper website (even if it's just a single headline initially and you have to look up every word). Then work your way up to paragraphs, articles and eventually books.
- I never practiced writing much (except when memorizing individual Chinese characters), but if you can speak and read, you can probably write. If your target language has a different keyboard layout, figure out how to switch to it in your OS and practice typing. For Linux, I can't plug Fcitx enough, especially for its awesome Unicode input feature.
- Finally, nothing motivates more than putting yourself into a situation where you have no choice but use your language. After 2 years of studying Chinese, I somehow managed to rent an apartment in China using only my still pretty limited speaking ability and the pressure of that and similar situations has helped me improve tremendously.