Wash the glass with car shampoo and water
Dry the windows with a clean microfiber towel
Apply white vinegar to a microfiber cloth
Wipe the water spots with the vinegar-dampened cloth
Let the vinegar sit for a minute on stubborn spots
Rinse the glass with clean water
Dry the window completely
Use a glass cleaner for remaining residue
Apply a dedicated water spot remover if needed
Use a clay bar on the glass for mineral buildup
Polish the glass with a glass polishing compound
Repeat the process on stubborn areas
Seal the glass with a rain repellent or glass sealant
Avoid cleaning in direct sunlight
Use distilled water for final rinsing if possible