The best library for self-learning {German} through digital and analogue.

Strategic mistakes:

• Studying intensely for limited periods instead of doing something every day consistently: My learning experience was like a roller coaster over ten years. I often treated German like a steep hill. My thinking was, "let's get over this hill as fast as possible." I started and finished many intensive evening courses, and at the end of each course I saw some improvement but not enough to use German in my social and working life, so over time my knowledge faded away again. I now understand that was a mistake. Structure in language learning is overrated and consistency is underrated. Learn messily, learn what you need on the spot, learn phrases and words here and there, take notes and lose them many times, but do something every day and use it every day.
• Not learning nouns with their gender and plurals: Unlike in English, learning the meaning of a word in German only accounts for about 25% of the learning. I think I know thousands of words and even understand the context most of the time when people speak to me in German, but I am not able to write or speak fluently because of this single problem. In German, learning a word means: 25% the meaning, 25% gender and plural, and the other 50% is being able to make a sentence with it.
• Not making sentences with new words: Science tells us that in order to make new words stick in our memory, we need to build connections between the word's sound and spelling and the things we already know. See mnemonic techniques. An actual mnemonic technique is more involved than just making a sentence with the word, but I think this is a really good method compared to brute-forcing our brains to memorize sounds and spellings that mean nothing to them. Imagine a scenario where you need that word in a sentence and play out that scenario while speaking it aloud.
• Not doing any mirroring, i.e. repeating out loud sentences you heard or read and understood: I remember how I learned English in high school. I had the luck of getting the best teacher. What she did was make us perform a 3-5 minute theater piece each week. Everyone had to memorize the whole text since players and roles were assigned randomly on the spot. It was a pure genius method because not only did we improve our pronunciation, we also spoke the language we were learning, we heard ourselves speaking it. Now I don't have access to a theater or a class (an absolutely gorgeous idea if you do or can organize one yourself). The closest thing you can do on your own is mirroring. Repeat a scene from a TV series you are watching, repeat sentences you liked out loud without looking at the text while reading. It is incredibly effective to hear yourself speaking the language you are learning.

Psychological setbacks:

• Not having fun: I learned German after my seminars during my master's, then after work in the evenings while working full time. I was either too tired or too stressed, so it was never a fun activity for me. And when your neurons are not happy, they don't fire, they don't build connections, and they don't build the language software in your brain. For most of us with busy lives, it is probably not easy to set aside an energized time for learning, but any effort to make it a fun and enjoyable experience, and to keep an elevated mood for it, will make a difference.
• Having mental barriers: Deeply connected to not having fun, thoughts like "German is too hard" or "life is too short to learn German" create barriers in our brains. We make it hard for ourselves by reinforcing these ideas.