This should be your first sentence, so the reader knows what you are trying to prove. Clearly state the issue and explain why it is important. Keep sub arguments together. A sub argument usually takes one to three paragraphs to develop. Make the conclusion of the sub argument the first sentence.
Support claims with evidence.
Then give the evidence that will justify belief. Do not assume the reader will understand what you mean. Define key terms. Use appropriate modalities. You must use a deductive argument form in order to prove a claim with a high modality.