"Buy Green, Buy Fair, Buy Local, Buy Used, and most importantly, Buy Less"

Surely that message is plain enough to understand and follow?
If you were too busy generating trash, you most likely didn't find the time to calculate your human footprint. If you can, do spare the time for The Story of Stuff - a 20-minute video on (what's wrong with) the material(istic) economy and mindless consumerism.
What presenter Annie Leonard conveys to the viewer is a simple axiom - A linear system of consumption in our finite world is unsustainable. The viewer is conducted through harsh facts of consumer goods production - extraction of natural resources, factory process, distribution in the market, consumption levels and goods disposal. The presenter frankly admits all the wrongs in the average American's consumption pattern - the Government-Corporate nexus, the exploitation of the Third World, the addition of enormous amounts of toxins - yes, toxins - energy, and natural resources to produce toxic products and by-products.
So, whatever kind of consumer each of us is, we could try to be more responsible by trying to "Buy Green, Buy Fair, Buy Local, Buy Used, and most importantly, Buy Less".