All you need to do is to take a big 35l bag, and pick up in the street or, even preferable in the nature, some trash on the ground that is not supposed to be there. Usually drink cans, beer glass bottles, plastic bottles and sweet wrapping are the usual type of trash you can find.

Once this is collected do not forget to bring it to the trash collection points near your home.

Also wear gloves and avoid dangerous types of waste you might find.