It would be a good idea to do some research on your topic. Looking at different sources should give you a good range of perspectives on the issue. You could try organising your main points in a similar way to your approach to an argument analysis - a clear contention, three main points with supporting evidence and a range of persuasive devices embedded in these main arguments. I'm not sure if you want to use a persona or just be yourself - your teacher might have a view about what they're looking for. Also, consider your audience - who are they, why should they care about your views? Think about the ways you can express yourself that will engage these particular people and keep them interested. I hope this is helpful, it's not clear what stage of preparation you're up to, what aspects of this style you have difficulty with or what the limitations of the task are (ie word length, choice of topic).