Congrats on 176! Did you have a tutor through 7sage?

Also drill, drill, drill! And thoroughly review each question after (whether you got it right or wrong). Validate yourself on the correct answers, and work to understand what you missed in the stimulus on the ones you get wrong. It's all about training your mind to notice where the argument is lacking.

Weaken questions have always been a category I struggle with. I think the most basic advice I can give is to look for ways to argue with the stimulus. In my head, as I am reading the stimulus for weaken questions, I try to think about what I would say if I were to argue with the author. Also remember that you're trying to disprove the conclusion using the premises (finding a flaw in the premises' reasoning/relationship), so be sure to know what the conclusion of the stimulus is. Hope this helps!