Install white window shades, drapes, or blinds to reflect heat away from the house.
Install additional attic insulation at right angles to the previous layer. You don't have to use the same type of insulation - it's fine to use batts or blankets over loose-fill, or vice versa. Upgrading from three inches to 12 inches can cut heating costs by 20 percent, and cooling costs by 10 percent.
Mild winters mean more chimney fires! It's true. People choke back their woodstoves in mild weather - leading to more creosote accumulation - but many don't realize this, so they skip getting it cleaned, thinking it doesn't need it as bad as it would after a cold winter.