Read “Coercion: why we do what They say” by Douglass Rushkoff. Learn about the ways you are manipulated into buying stuff you don’t need.
Support replacing the income tax code with sales taxes so that everyone sees the actual cost of buying stuff and going to war. Don’t be mindlessly pedantic about “sales taxes are regressive” without thinking about how regressive a dead planet will be. Negotiate the size of the prebate in order to make it progressive. Don’t blindly believe that the people who get rich and elected from consumerism are going to do anything to stop destroying the planet when they depend on someone getting rich in order to tax them.