To professionally clean a window, a window cleaning service will typically begin by removing any dirt or debris from the window's surface using a soft-bristled brush or a microfiber cloth. They will then apply a specialized cleaning solution that is designed to break down and dissolve any stubborn dirt, grime, or water stains on the glass. Once the solution has been applied, the window will be squeegeed clean, removing the cleaning solution and any remaining dirt or debris. To ensure that the window is streak-free and completely clean, the edges and corners will be wiped with a lint-free cloth or chamois, leaving the window sparkling and clear. Finally, the window cleaning service will inspect the window for any remaining spots or streaks and touch up as necessary to ensure that the window is perfectly clean and looking its best.