What is the best way to repair rotted wood on the exterior of a house using exterior wood filler?

To repair rotted wood on the exterior of a house using exterior wood filler, start by removing the rotted wood and cleaning the area. Apply the wood filler according to the manufacturer's instructions, making sure to fill in all the damaged areas. Sand the filler once it's dry, and then paint or seal the repaired area to protect it from further damage.