Honestly the only way that things stuck with me was when I was forced to use the language (i.e. immersion). Previously I persuaded my wife to only speak to me

Honestly the only way that things stuck with me was when I was forced to use the language (i.e. immersion). Previously I persuaded my wife to only speak to me in her native language every Thursday afternoon/evening. That helped a little, but only when I moved and was surrounded by the new language did I really get better. It took me months to learn to hear AND pronounce the difference between "o" and "ö", and still I get it wrong at times.