Brаinstоrm the purpоse. Write аny аnd all ideas yоu have about the purpose for this topic. Do not worry if the ideas are good or bad. Why are you writing this? What do you want the reader to do or believe? Choose one specific purpose: to change someone's mind or to get someone to do something. As you brainstorm, keep these questions in mind: Are you trying to change their mind? Are you trying to get them to take action? Are you proposing a solution to a problem?