I feel like most days around here are Earth Day in any case. I remember as a teenager, collecting aluminum cans was something we did for church fundraisers. Nowadays it's far more in vogue; our recycling bin is much bigger than our trash can at the moment.
We do our best around here to reduce, reuse, and recycle, but we don't obsess over it. I still use paper towels on occasion (after all, how else do you grease your cast iron pan?) and when we're out and about, we still buy a bottle of water when we're thirsty (usually after my glass bottle is completely empty!)
But for the most part, we try not to waste food or electricity, and we tend to repair items in our household before we replace them. When we do have to replace them though, we usually donate the older item to a thrift store. (The Sailor is not a fan of clutter... and I have to say that most days it makes me crazy as well, even though much of the clutter stems from my own craft supplies. Here are more tips for Spring Cleaning, plus some tips on decluttering the craft supplies.)
And, of course, we plant stuff. We have a vegetable garden going at the moment, and now the porch is a perfect little plant haven for those times we want to sit outdoors.
Happy Earth Day, every day!