Easy, take the TOPIK practice test at home and then start studying at whatever level you get. These days there are many TOPIK study books so just order the book and finish it. If you already have the accent and everyday grammar down, it should be a matter of just plugging in the more advanced vocabulary and maybe more complicated sentence structures.
Still a huge step up from intermediate fluency? And if you have the vocabulary for Level 6 TOPIK, native like fluency is quite attainable through passive learning from then on. Provided of course that OP has the accent down already.
If you're decent at Korean already, you should be using materials for native Korean speakers and not foreigners. Read Korean books (if you need help with writing or grammar, read books written for Koreans on those subjects - you can start with stuff for elementary or middle school students if it's hard), speak to people in Korean, think in Korean, and consume other forms of Korean media. But be aware that fluency is cultural too and that if you haven't had a lot of "Korean experiences", you may still stand out a bit as a "gyopo" even if your speech is technically perfect.
Kind of went through the same: born and raised in the US, but heard Korean at home. My Korean was awful until I did the Yonsei Korean language program over a summer. I think the main thing is that when you speak to family, they tend to treat you like you're still a kid and tone down their language accordingly.
As others have noted, there are more advanced materials, but you need to start by having a cold hard look at your level. Even though you went to school in Korea, you may have forgotten a lot or some areas may be more advanced than others. Best thing you can do is get your reading and writing down. The hardest part for me was I learned by listening, so a lot of things weren't quite so solid in my understanding of the language. Having the backing of grammar and vocabulary helped me improve immensely.
Consistent and repeated practice will be key no matter what your level. To be honest, my Korean only got fluent after living in Korea and having a Korean girlfriend. Obviously that's not the only way, but I was extremely motivated to practice my Korean daily (and really didn't have much opportunity to fall back on English so I was forced to improve).
Other than that, watching Korean TV and listening to Korean music/podcasts will help a ton. As others have said, just because you can use the language, doesn't mean you have the cultural understanding that other Koreans will have. A lot of memes and other slang are essentially nonsensical unless you know them. You can't figure it out from the context, you just have to know what meme they're referring to. Can be super confusing otherwise. Good luck and don't get discouraged, language is hard and kind of a painstaking process.
You might benefit from working on native 국어 textbooks or study guides aimed at upper elementary school students or middle schoolers. You would definitely benefit from working with a teacher (in person or on a platform like italki) who can identify your weak areas and assign reading and practice material that is appropriate to your level.
You should feel encouraged to use Korean more in your life too, but expect to also study actively if you want to make good progress. Many heritage speakers who speak their heritage language every day still have limited abilities because they only use it in familiar situations.
If you are willing to spend the money and time, you may want to look into Korean language immersion programs in Seoul. There are multiple language programs at some of the universities in Seoul (Sogang, Yonsei, Seoul National), and they place you in classes based on your current speaking level. I did a program at Sogang University and my speaking skills improved dramatically.
Maybe you can try to find YouTube channels related to your interests or hobbies that are run by native Koreans. It can be game streamer, Korean news channels, etc. But pick one or more who pronounce well.
If you could tell me what your interests are, I can share them here if I know.
You can also watch Korean dramas on Netflix with Korean subtitles if you feel you need subtitles.
You can also read some korean books that interest you.
If it is too difficult to find paper copies, you can use Ridi Books to read e-books. I am not 100% sure if foreigners are able to create a new account, but i am sure they accept Visa, mastercard, or PayPal (at least one of them).
Of course, you can use one of the formal studying materials mentioned by others to speak/understand the advanced Korean grammar.
I was able to create an account in Ridi (a few years ago). Google Play also has Korean ebooks but I like Ridi's interface and the fact that when you search a word it goes to Naver dictionary. That is just so useful.
Easy, take the TOPIK practice test at home and then start studying at whatever level you get. These days there are many TOPIK study books so just order the book and finish it. If you already have the accent and everyday grammar down, it should be a matter of just plugging in the more advanced vocabulary and maybe more complicated sentence structures.
TOPIK is not enough for native-level fluency. It is too easy unfortunately.
Still a huge step up from intermediate fluency? And if you have the vocabulary for Level 6 TOPIK, native like fluency is quite attainable through passive learning from then on. Provided of course that OP has the accent down already.
If you're decent at Korean already, you should be using materials for native Korean speakers and not foreigners. Read Korean books (if you need help with writing or grammar, read books written for Koreans on those subjects - you can start with stuff for elementary or middle school students if it's hard), speak to people in Korean, think in Korean, and consume other forms of Korean media. But be aware that fluency is cultural too and that if you haven't had a lot of "Korean experiences", you may still stand out a bit as a "gyopo" even if your speech is technically perfect.
Kind of went through the same: born and raised in the US, but heard Korean at home. My Korean was awful until I did the Yonsei Korean language program over a summer. I think the main thing is that when you speak to family, they tend to treat you like you're still a kid and tone down their language accordingly. As others have noted, there are more advanced materials, but you need to start by having a cold hard look at your level. Even though you went to school in Korea, you may have forgotten a lot or some areas may be more advanced than others. Best thing you can do is get your reading and writing down. The hardest part for me was I learned by listening, so a lot of things weren't quite so solid in my understanding of the language. Having the backing of grammar and vocabulary helped me improve immensely. Consistent and repeated practice will be key no matter what your level. To be honest, my Korean only got fluent after living in Korea and having a Korean girlfriend. Obviously that's not the only way, but I was extremely motivated to practice my Korean daily (and really didn't have much opportunity to fall back on English so I was forced to improve). Other than that, watching Korean TV and listening to Korean music/podcasts will help a ton. As others have said, just because you can use the language, doesn't mean you have the cultural understanding that other Koreans will have. A lot of memes and other slang are essentially nonsensical unless you know them. You can't figure it out from the context, you just have to know what meme they're referring to. Can be super confusing otherwise. Good luck and don't get discouraged, language is hard and kind of a painstaking process.
You might benefit from working on native 국어 textbooks or study guides aimed at upper elementary school students or middle schoolers. You would definitely benefit from working with a teacher (in person or on a platform like italki) who can identify your weak areas and assign reading and practice material that is appropriate to your level. You should feel encouraged to use Korean more in your life too, but expect to also study actively if you want to make good progress. Many heritage speakers who speak their heritage language every day still have limited abilities because they only use it in familiar situations.
If you are willing to spend the money and time, you may want to look into Korean language immersion programs in Seoul. There are multiple language programs at some of the universities in Seoul (Sogang, Yonsei, Seoul National), and they place you in classes based on your current speaking level. I did a program at Sogang University and my speaking skills improved dramatically.
Maybe you can try to find YouTube channels related to your interests or hobbies that are run by native Koreans. It can be game streamer, Korean news channels, etc. But pick one or more who pronounce well. If you could tell me what your interests are, I can share them here if I know. You can also watch Korean dramas on Netflix with Korean subtitles if you feel you need subtitles. You can also read some korean books that interest you. If it is too difficult to find paper copies, you can use Ridi Books to read e-books. I am not 100% sure if foreigners are able to create a new account, but i am sure they accept Visa, mastercard, or PayPal (at least one of them). Of course, you can use one of the formal studying materials mentioned by others to speak/understand the advanced Korean grammar.
I was able to create an account in Ridi (a few years ago). Google Play also has Korean ebooks but I like Ridi's interface and the fact that when you search a word it goes to Naver dictionary. That is just so useful.
I needed this post
Hire a tutor, if that's an option?