30. Buy a Reusable Water Bottle

Reusable water bottles are good not only for the environment but also your wallet. This one-time purchase ensures that you’ll no longer have to buy bottled water at the store. 
But this is just one example of how you can swap everyday expenses, be they big or small. Think of something you buy regularly or semi-regularly and consider an alternative. The zero-waste community that encourages people to be more mindful of the environment often point out how eco-friendly items are also much easier on their finances, so it might be a good idea to check out some of their ideas and see what fits your lifestyle and what you can swap in order to save money.