- saving electricity at home with efficient light bulbs, efficient appliance, and solar panels;
- saving gas by driving less and driving more efficiently; and
- saving trees by using cloth napkins, conserving office paper, and reading the news online.
And that's just the ways to save water inside the house; you could write a whole book (and, in fact, many people have written books alredy) on all the things you can do to reduce water use in the yard. So even though this article is very long and very detailed, there are some topics on which it really just scratches the surface.
But if all you need is a basic primer how to save water at home, indoors and outdoors, then I feel like this piece covers all the bases pretty well. You can read it here: Ways to Save & Conserve Water at Home (Indoors & Outdoors).