Three ways you can save energy on any day or earth day are Turn lights off that are not needed or turn lights off when you leave a room.
If you have a dishwasher only run it when it's full and the same goes for the washing machine, you can also save energy by hanging your clothes out to dry instead of using an electric or gas clothes dryer.
Clothes dryer's and especially the electric ones use around 4,000 5,000 watts so not using a clothes dryer and hanging out your clothes can save a ton of energy.