Pick up the pop top, clean up the camp site, remove the litter from your street, even if you didn't put it there. Minimize your contribution to the world's pollution. We all pollute, to a greater or lesser degree, but we can all reduce the amount that we pollute. Recycling, voluntary simplicity and simple consideration of others are all ways to begin. Stop tolerating irresponsible behavior.
Some people are irresponsible by choice, some by habit, and others by ignorance.
Whichever the cause, you can begin to make a difference by letting the other person know, in a nice way, that his or her behavior is unacceptable. The key here is to address the behavior rather than the person. Add your voice. If you're an observer of the political scene, you might well conclude that your voice and vote are of little value and, in many areas, that's true. It's also true that the communications revolution, especially e-mail and instant phone polling, is slowly changing that.