A speak out allows people to testify about their own personal experiences. Hold a Tribunal. A tribunal is a panel of judges who hear testimony about a crime. The crime could be hunger, the actions of a particular polluter, or those who commit war crimes. Organize a Town Meeting.
Many organizations testify about a problem.
Often a public official or decision maker is present. File a lawsuit. Hold a Street Fair. In a festive atmosphere, have tables where people can get information. Put up Posters.