Unplug unused appliances like your laptop charger, toaster, and phone charger. These can gradually drain electricity and, over time, inflate your monthly electric bill. You can also group all of the electronic appliances in a room on a power strip, which can be turned off when the appliances are not in use, simplifying the process while still leading to savings.
Squash your rolls of paper towel or toilet paper, which will remind you and gently force guests to use less paper.
Buy generic household cleaners for a discount, or better yet, perfect your own recipe by using a mix of baking soda and vinegar. These household staples are more than capable of cleaning nearly any surface in your home.