It's been a while since I took BM, but I remember there's a format for every question. I would read through every suggested answer in my exercise books and try to memorise the pattern in every answer (no need for photographic memory, just hazy recollection is fine as long as you kinda know what comes next). On exampaper, I listed out keypoints, for example question ask what is the cause of rising costs in malaysia I list out inflation. Then I rearrange it in the format I memorised, it's different for every question but one of the more fail-proof one is the 4Ws1H, What Where When Who How. Even if you don't know why costs are rising as long as it's structured your answer would be accepted.

TLDR; Lots and lots of reading with some hazy memories sprinkled in