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1. I try to avoid buying bottled water as much as possible.  Hopefully, not at all in the years to come.  Bottled water uses up more water than just drinking tap water.  Also, plastic bottles that need recycling (recycling is good, but why waste energy recycling something you can avoid buying in the first place?).

2. I try to not use plastic bags.  Instead, my mom, dad, and I have been buying those reusable bags they sell for like... 99 cents.

3. Lights, etc. that aren't being used are ALWAYS turned off.  My MacBook doesn't stay on if I'm not using it.

4. We usually use those energy-saving light bulbs.

5. I recycle ALL paper.  Seriously.  Even like... Post-Its...

Basically... Reduce, Reuse, Recycle.