1-Choose the right time and place. When washing your car, cleaning and polishing the windows should be the last thing you do. You should also clean the glass while working out of direct sunlight, while the windows are fairly dry. Otherwise, the sun may dry out the glass cleaner, leaving streaks behind.
2-Select the right supplies. A glass cleaner specifically labeled for automotive use is better than an ordinary household glass cleaner, which often contains ammonia and other chemicals that can be dangerous for use on cars. A microfiber towel is also a necessity, since it has enough abrasiveness to gently scrub the surface of the glass without scratching it.
3-Roll down the windows halfway. You need to be able to have clear access to the top edge of the glass.
4-Spray the glass cleaner on the window. Clean the glass by wiping the cleaner onto the window using your microfiber cloth, moving from side to side. Cover both sides of the glass.
5-Use the dry side of the microfiber cloth. Remove any remaining wetness on your windows by drying them with the dry side of the cloth.
6-Roll your windows up and clean the bottom half. Spray with glass cleaner, wipe the cleaner on, and wipe the cleaner off.
7-Clean your front and back windshields. Spray the cleaner on the windshields and wipe it with your microfiber cloth, moving both up and down and side to side. Remove the dampness with the dry side of your cloth.
8-Rinse with water. Once the stubborn grime has been cleaned off your windows, you can remove any streaks or film with clean, plain water. Gently spray the glass, using a hose for the outside and a spray bottle for the inside. Wipe the glass dry with a clean microfiber towel.