Stop for a minute and think about the impact you are having on the planet. What action of all of your daily actions makes the greatest impact? That's where you should start. You don't need to change your entire way of living, change the biggest impact points that you can spare.

This is a well known mantra that you can use: "Reduce, Reuse, Recycle".

Reduce

Don't buy things you don't need. Everything that is produced requires energy and resources, both of which affect the planet in a multitude of ways; toxins, greenhouse gas emissions, deforestation etc. By not buying so much things you also save yourself some money, take a longer vacation!

Reuse

By reusing things that still work, everything from clothes and books to building materials you avoid having to buy new things! Care should be taken tough, it might be better to buy a new dish washer if your old one uses a lot of energy for example.

Recycle

Certain things we use in our daily life is well suited for recycling. That includes glass and metal. These materials require a lot of energy to produce from scratch, and a lot less when recycled. So try to recycle everything from jam jars and beer bottles to soft drink cans. Other materials that we use on a daily basis are hazardous to humans and the great animals of our planet. That includes batteries, your old TV, the broken MP3 player etc. These should be recycled as well.

Here's another list of simple things to do:

1. Buy Energy Efficient (car, washing machine, refrigerator etc)
2. Change 5 lights (from incandescent to LED or CFL)
3. Look for ENERGY STAR qualified products
4. Heat and cool smartly
5. Seal and insulate your home
6. Use green power
7. Be green in your yard
8. Use water efficiently
9. Spread the Word