I know, but in school I was good in english and now I forgot all
but count me in, I'll try.
I've got something that worked perfectly well when it came to preventing me from forgetting too much: Whenever I want to see a movie or read a book that's originally in English, I'll see/read it in English. The movies were pretty hard to understand at first, but by now I don't even think about any words that I don't know. My brain doesn't even realize if I don't understand some of the words in a sentence because it's all perfectly clear from the context. And if my brain does go "WTF", it's probably because most native speakers would react in just the same way
Books are just the same, just without the really hard part in the beginning.
And even though I never really use the language myself, I don't really have any problems right now. Maybe not everything's really correct when it comes to grammar or figures of speech, but I still don't have to think much more about how to write something than I'd have to in German. Actually, sometimes I know perfectly well how it should sound in English but I just can't remember how one would put it in German
For example, every single time I think about pumpkins, I really have the word pumpkin in mind instead of Kuerbis. And every single time, i need some time to remember what it's called in German
Guess I read too much Harry Potter
And as there is a pretty high chance that we'll one day really need the language
in real life, I can only recommend this method of not forgetting
It's definitely worth it, and once you get used to it, it doesn't make a difference anyway, which version of a movie/book you use - except that with the original, you don't have to bother with translation errors and those little word plays that just don't work in other languages. Free practice with things that you'd do for entertainment anyway!