Mastery comes from practice. If a software developer wants more experience with a language, a tool, or a platform, there are many ways to get this experience, like joining or starting an open source project. However, if a software developer wants more experience managing and leading people, it is less obvious how to do this.
Has anyone made a deliberate and successful attempt to practice leadership? What have you found effective? What recommendations do you have?
I assume someone will suggest using open source projects to develop leadership skills. How does one effectively provide leadership to an established group after joining it? How does one grow a new project?