Discussion questions technique

Hi tutor, The nerves are really setting in now! When it comes to discussion questions within the exam I often find that I am wasting valuable time trying to introduce the topic and set the scene before really getting into my answer. How do I stop myself from wasting valuable time so I can just get down to addressing the scenario in the question? 1 more cheeky question.... What would be your advice to tackle the often neglected Question 4 when you realise that you are running out of time and are not able to allocate the 1.8 minutes per mark to it as required? Thanks for everything Opentuition!