When it comes to persuasive speeches, most speakers choose to use a problem-solution organization. There are two key strategies that you might consider using:
Problem-solution:
Identify, define and explain the problem
Identify and explain the solution, providing actionable steps
Monroe’s Motivated Sequence:
Attention – Get the audience’s attention (often using a statistic or notable fact)
Need – Demonstrate that there is a problem that needs to be solved
Satisfaction – Identify a solution to that problem and why it is the best course of action
Visualization – Explain what will happen once the problem has been solved
Call to Action – Tell the audience a specific plan of action that they can take to help enact the solution
Remember in a public speech, you still need to include a full introduction and conclusion, in addition to effective transitions in order to help the audience follow along.