>>96865
>look up stuff, forget them right after
That's exactly like me. I used to think that the worst offenders there are rikaisama and the likes, because it takes zero effort to look up a word, but the thing is even if I have to manually discern some random kanji and look it up a dictionary manually, it only marginally sticks better. Whatever I don't put into anki, save for a few exceptions, I forget completely.
Also tip, even if you use anki, you don't have to put every single unknown word into it, especially if you're a beginner. You'll just overwhelm yourself with words and learn a lot of words that you'll barely see again (if at all), only add common words first. (And by common I mean common in the stuff what you're trying to read, and not common according to core6k/10k or rikaisama word frequency which is based on newspaper word frequency counts I think).
>lots of uses
In that case I just list all uses on the card. Yeah, this means that sometimes I get 3-4 lines long definition., but I can't really think of a better solution.
>collocations
What I do is to list the words with similar meanings on the card,that can help a bit if you see all similar words and meanings in one place. Of course, it's not perfect, you can't reduce all the nuances into a few words definition, for that you have to read a lot. And to read a lot, you need a lot of vocabulary first, otherwise you'll have to stop at every third word to look it up in a dictionary, which is like the surest way to burnout.