Hair conditioner for shine
Wash your car with a hair conditioner containing lanolin. You'll become a believer when you see the freshly waxed look, and when you find that the surface will repel rain.
Fizz windshields clean with cola
When it rains after a long dry spell, a dirty windshield turns into one big mess. Get rid of streaks and blotches by pouring cola over the glass. (Stretch a towel along the bottom of the windshield to protect hood paint.) The bubbles in the cola will fizz away the grime. Just be sure to wash the sticky cola off thoroughly or your cleaning efforts will end up attracting dust and dirt.
Vodka on the job
When your windshield-washer reservoir needs filling, raid the liquor cabinet to make your own washing fluid. In a screw-top gallon jug, mix 3 cups vodka (the cheapest you can find) with 4 cups water and 2 teaspoons liquid dishwashing detergent. Screw on the cap and shake well, then pour as much fluid as needed into the reservoir.
Shine those car lights
Keep your headlights polished (and yourself, safe) by applying window cleaner and rubbing vigorously with an old pair of panty hose.
A one-step window cleaner
Clean your windshield and car windows by rubbing them with baby wipes stored in your glove compartment. What could be easier?
No windshield washing fluid?
If the reservoir is empty (and doesn't it always seem to be?), use an unlikely substitute to clean your windshield: feminine hygiene maxi-pads, a box of which you could stash in the trunk. Hold a pad on the sticky side and rub the windshield vigorously. The glass will really shine once you've wiped it to the max.
Clean your blades
If your windshield wiper blades get dirty, they'll streak the glass instead of keeping it clean and clear. Make a solution of 1/4 cup household ammonia to 1 quart cold water. Gently lift the blades, and wipe both sides with a soft cloth or paper towel soaked in the solution. Then wipe the blades with a dry cloth before lowering them into place.
You can see clearly now
Add 1/4 cup household ammonia to 1 quart water, pour it into a plastic bottle with a water-tight cap, and keep it in your car for washing the windshield and windows. As soon as your windshield begins to get dirty, take out the solution and apply it with a sponge; then dry the windshield with a soft cloth or paper towels.
Baking-soda car cleaner
Pour 1/4 cup baking soda into a gallon-sized jug, then add 1/4 cup dishwashing liquid and enough water to fill the jug almost to the top. Screw on the cap, shake well, and store the concentrate for later use. When it comes time to wash the car, shake the jug vigorously and then pour 1 cup of cleaner base into a 2-gallon water pail. Fill the pail with warm water, stir to mix, and your homemade cleaning solution is ready to use.
Banish back-road dirt
In many rural areas, so-called oil roads (some unpaved, others semi-paved) are sprayed with oil to control blowing sand and dust. If you find yourself driving along one of these back roads, your windshield may end up coated with oily grime. To cut through the muck, sprinkle cream of tartar over the windshield, and then wipe the glass down with soapy water, rinse well, and dry.