You can do a lot yourself to live green yourself, but there are some projects that are necessary yet too large for you to accomplish alone. For example, conducting research in clean energy, building solar power plants, or carbon sequestration projects. Civilization is founded on the idea that people band together, in time and by contributing resources or money, to create projects larger than they could do alone. Think of the old-fashioned barn raising.
To help support these kind of larger projects, you can purchase Green Credits, which support sustainability projects and scientific research in sustainability, retiring carbon offset credits, planting trees, or buying the most polluting cars off the road,