Many of us use very large capacity water tanks to flush our toilets. One way to quickly and easily save water is to put one or two bricks inside the tank. Saving a half-gallon of water EVERY time you flush will save money in energy used to treat and clean the water, and it will keep the associated CO2 emissions from polluting our atmosphere.
When not using appliances or electronics, unplug them. Keeping them plugged in, even when turned off, still consumes electricity. This is especially true with cell phone chargers.
When you are washing your hands, don't leave the water running. Since you should be scrubbing your hands long enough to be able to sing the ABC song, that's a long time to leave the water running, especially if you aren't actively using it. Turn it off after you wet your hands, and back on when you're ready to rinse. You'll save a lot of water.
When you go to a fast food restaurant, think twice about the trash you throw away. A lot of the containers you get your food in can be recycled. Ask for a bag, and bring home any recyclables to throw in your recycling bin at home.
Say no to plastic/paper bags at grocery stores. Buy a pair of big reusable tote bags at Costco for just $1.50. Whole food donates a nickel to your choice of charity every time you say no to plastic/paper bag.
Instead of shoving all those food scraps down the disposal, build a vermicompost bin. It's easy, you get a rich compost fertilizer from food scraps and it's fun! Get the kids involved too. My 2 year old daughter sings to the worms while she dumps her food scraps into the bin at night. The link below is a pretty simple version but works just fine.
You can opt out of the catalogs that fill your mailbox using "Catalog Choice" at http://www.catalogchoice.org/. The site allows you to select which catalogs you want to receive and which ones to opt out of all in one place.
Keeping your tires inflated to the proper pressure can improve your gas mileage by up to 3.3 percent. It's also safer, and will make your tires last longer (which ultimately results in less waste).
Look for biodegradable doggie poop bags for cleaning up after your pooch. There's a lot to clean up after over the life time of your dog. Help it all return to earth faster by avoiding non-biodegradable plastic baggies.
You know those 50 napkins you usually get with fast food meals? Don't throw them away when you're done. Put them with the rest of your paper napkins and use them for causal meals (probably not when you have guests over). Save some trees, and save yourself some money.