1. Herb Garden
One of the best ways to become more sustainable in general is to grow your own food. This can be a pretty daunting task, so it's easiest to take baby steps. I grow basil on my window ledge, rosemary in my backyard, and I have a lemon tree by my garage. This isn't a lot and it's pretty simple to maintain, but those are three fewer foods you'd need to have a company grow, package, and ship to your store. The closer you can bring the food process to your own home, the greener it is.
2. Bee Watering Hole
Bees are extremely important for pollination and food production. Unfortunately, the bee population is in distress and might soon be considered endangered. You can make your yard a haven for our yellow friends by giving them a safe place to drink. Bees need to hydrate just like every other animal but often drown trying to get water. Get a dish or bowl, fill it with rocks, and then fill the bowl with water just below the rock line. The bees can reach the water while still staying dry. Just make sure you keep their water fountain away from areas with kids or pets.
3. Compost Pile
Having soil with tons of nutrients is really important for your new herb garden. Healthy soil will keep your plants happy and thrive. Instead of paying for compost of bagged soil, you can do all of this yourself with things you'd throw out anyway. All of the coffee grinds, kitchen scraps, and lawn trimmings that would get tossed into the garbage can be composted for your soil. Put everything in a bin with some worms and let nature work its magic.
4. Rain Water Collection
Something else that's really great for your plants is water. But we're also in a draught (for my Californians). Put a barrel or a bucket under your rain gutter pipe and save any water that collects to take care of your yard. That way you're not running water from your house and the rain water gets repurposed.
5. Low Maintenance Plants
An even better way to save water is to not use water at all. Fill your yard up with plants that don't need to be watered often: cacti, succulents, lavender, and aloe are a few good ones. You'll save a ton of water and your yard will still look great.