Although garages are often attached to a home, they are rarely equipped with the ability to self-heat. That's because most people use them simply to store their cars and other odds and ends. However, there are cases where a heated garage is nice. For example, it's common to set up a workshop in the garage, work on your car during winter or simply keep it warm throughout the year to protect stored items. Fortunately, heating your garage doesn't have to be costly.
Close all the windows and doors in your garage.
Seal off cracks around the window, garage door and any other entrance. Tape cling film over the cracks and roll up old towels to place at the foot of your door. This prevents cold air from seeping in and out which will instantly make your garage warmer.
Purchase a small, portable electric heater. Never use a propane or gas heater, as they emit fumes and are more prone to catching fire.
Turn the heater on only when it's necessary for the garage to be heated as this saves money on electricity. Point the heater toward the area you're working in. This will warm up that space more quickly.