Verified answer

It means that if you want to save the planet and stop pollution, start doing this yourselves. 

The earth is our home. We need to save it. 

First we must think what we have done.

To solve this problem we must start with ourselves, with our house, with our street.

If every person cleans his house and his streets our planet will be clean. 

Everyone must understand that one can do more than he or she ever imagines for the improving of the situation.