If you want to learn the German language as a second language, you will need to go to Germany to learn the language altogether. Thats what they do back when theres no internet, back when accessibility is difficult. Nowadays, if you want to learn the German language or even other languages for that matter, one click is all it takes.
Learning another language may take time but it would really depend also on the student. What you should really be asking is how you can learn and retain the foreign words that initially sound gibberish the first time you encounter them on the newspaper, from the radio or overheard from a foreigner down town.
Words like Guten Morgen, Guten Tag and Auf Wiederstein are common German words and you may have heard them from interesting movies or animated cartoons. But, think about this. When you overheard those German words, what picture immediately comes to mind? Is it an image of a funny looking talking creature from an animated cartoon hit? Or is it more like a picture of family singers?
As you may have observed, each memory that we have is always associated with a distinct event, character, persons and places. We may have forgotten...