The system I have always used to help make sure that you stay relevant to the question, as well as picking up as many points for discourse markers is as follows:
P - Make your Point, give an introductory sentence that should stand-alone to answer the question but which can also be built upon later.E - Evidence - how can you prove this? Give a statistic or anecdote which helps your point - you can make this up but don't be ridiculous - make it sound feasible.E- Evaluate - how far does this evidence go to back up the point you are making? is it the most convincing evidence?O - Opinion - give your own personal opinion on the specific point you are making, and where possible to the evidence too!G - Goma (Spanish for rubber) - can you 'ping' your answer and evidence back to the question - how is what you have said relevant and how does this help your conclusion?