Register for a first level Korean class at your high school, a local community college or a four-year university.
Purchase the textbooks, workbooks and all other necessary supplies that your teacher or professor requires. Your teacher or professor should inform you in their syllabus what materials are required. If they do not, do not hesitate to ask.
Attend every class period and participate as much as possible by responding to homework questions, speaking with other students in class and putting all of your effort into any games your Korean professor requires you to play.
Record detailed notes during each class period and ask questions whenever you are confused.
Complete all homework activities that you are assigned and make time to practice with other students in your class. Study groups can help make learning the Korean language a lot easier.
Read all of the Korean passages that your teacher assigns. Reading the language will help you absorb the language even if you don't understand every word you are reading.
Visit your local library and research what books the library has that can help supplement the learning that is taking place in school. Look for Korean language books, online tools and even Korean literature once you feel comfortable enough with the language.