In order to be a changemaker you have to propose yourself to do it and accomplish it. It's a goal you set yourself and a mindset you must impose to yourself to accomplish. The way to challenge yourself is to start by doing little things. For example: "You want to run 3 miles", so, start by running just 3 blocks. By doing this everyday eventually you will run 3 miles.
Now, to change the world you have to fight constantly. For example: PETA is an organization that helps fight against animal cruelty. They always assist protest, go to the government to be heard and risk their lives for the sake of the animals. The members are also vegan, they know where the produce cones from and decide not to eat or wear anything animal. These steps make sure that at least some animals aren't eaten or being harmed.