You may not think about your lawn as things cool down during the fall season, but it's actually the most important time of year to help it survive the cold winter months. As your grass absorbs nutrients to survive, you can help it thrive by doing one thing: aerating. At home improvement stores, you can rent a lawn aerator that punches holes in the soil. The holes allow water, oxygen and nutrients to easily reach the roots of the grass. It's simple to use and goes a long way to give you a healthy lawn come spring.