Tools

• Cotton and paper towels leave lint, dirtying up an otherwise clean window. For glass that is as clean and streak-free as possible, use a squeegee. Purchase a small one that fits all your panes of glass. Wipe across the top of a wet window with the first stroke, then make a series of downward strokes to completely dry the window.
  
  

Solution

• Skip the expensive spray cleaner and make your own effective window cleaner. Mix 1/2 cup of white vinegar with 1 gallon of warm water. If you don't have any vinegar, use the same amount of sudsy ammonia. Wipe the cleaner on windows with a soft cloth, or spray it using a clean spray bottle before using the squeegee to dry the windows.
  
  

Weather

• Wash windows on cool and cloudy days, or early in the morning before the sun has gotten high in the sky. The hotter and brighter the sun, the faster the cleaning solution will dry. Ideally, the cleaner needs to be removed with the squeegee before it dries on the window.
  
  

Detail Work

• Finish up the job by running a paper towel around the outside edges of the windows and along the bottom edge of the glass. This will remove any excess water that may have pooled on the window sill, and makes the final job look neater and more professional.