Weakening Questions

i have a lot of difficulty with weakening questions. although i know a weaken question means to attack the support between the premise and conclusion, i fear i don't really entirely understand that and that's where i keep picking the wrong answers. i know the correct answer might give an alt explanation, a reversed causation, undermine the data/sample, make use of a broken analogy, or missing information but i usually miss out on those answers and end up picking the wrong one. does anyone have any suggestions or can break down the concept for me in a way i can understand better?? it's so frustrating.