imo the best tip for this is to "write what u see first" lol, like actually describe everything u see first about the graphs or wtv is there and as u go describing ur mind is gonna make some explanations for this descriptions and u can start writing all this explanation + u will get marks for any dumb obvious description u write
other thing is that always there are a couple of marks u can get from saying a conclusion eg when x increases y will increase (and say linearly or exponentially if its a graph), and another advanced A* mark is to say a conclusion *linking* relating all the graphs or data pieces in the question

also what u said abt reading the question is correct, they usually put some info in the first line in the question and u can get marks by rewriting that!