Vacuum your
condenser coils. These coils
are usually located on the back of your refrigerator and can
accumulate a thick layer of dust over time. Clean these every six
months with your vacuum to avoid putting extra wear-and-tear and
your fridge.

Maintain the gasket.
The gasket is the rubber seal
that runs around the perimeter of your refrigerator door, and keeps
the warm air out. These gaskets are known to crack, which can cause
your refrigerator to lose cold air. Periodically wipe the gasket
clean with soap and water and apply a thin layer of Vaseline to keep
it from drying out and cracking.

Keep away from heat
sources. Keeping your
refrigerator away from sources of heat reduces the amount of work
that the compressor must undergo in order to maintain a cold
temperature. This includes heat-generating appliances such as your
stove, but also avoid exposure to direct sunlight if possible.

Avoid keeping the
door open. Every time you open
your refrigerator door, you lose a little bit of cold air. Keeping
the door open for long periods of time will cause you to lose more
than just a little warm air, and your refrigerator will have to work
harder to cool down. When you are making a recipe which calls for
multiple refrigerated items, take them all out in one trip and try
to avoid staring into an open fridge looking for something to eat
(hey, we all do it!).