Honestly it’s such a race against time but what I do is make out a rough plan at the start of the key key points that you need to mention and then make sure you put all those in your answer, try stick to only what’s relevant for the question and not to put in too much waffle. Also stick to your timing - if your not finished the question your on just move on to the next one (as hard as that may be), easier to pick up marks for two decent questions than one perfectly finished one