Mix a solution of 2 tablespoons cornstarch and about 1/3 gallon of lukewarm water in a bucket.
Saturate a lint-free rag or paper towel and wipe the glass. Stubborn stains may require some elbow grease or gentle prodding with a fingernail.
Dry the frosted glass with another rag or paper towel and marvel at the shine and absence of streaks.
Mix a 50-50 solution of white vinegar and water in a bucket.
Dip a rag or paper towel in the solution and then wipe the frosted glass.
Wipe the glass again with a dry rag or paper towel.
Apply white vinegar to the glass, full strength, if the 50-50 solution fails to lift the hair spray. Like cornstarch, vinegar is a workhorse glass cleaner.
Saturate some cotton balls with rubbing alcohol.
Wipe the frosted glass and apply pressure, as needed, to the hair spray deposits.
Wet a lint-free rag or paper towel with warm or cool water and wipe the glass to remove all traces of the alcohol.
Wipe the glass clean and buff it to a shine with a clean rag or paper towel.