There is more than one effective way to clean your windows. One inexpensive method is to start by making your own cleaning solution by adding warm water and a teaspoon of dishwashing soap to a 5-gallon bucket. Scrub the window with a scrubber or clean sponge that is damp with washing solution. Then, starting at the top, wipe off the solution with a lint-free cloth or a squeegee. If using a cloth, try to have only dry areas contacting the window at each pass. For the best results, wash the windows when they are not getting direct sunlight.