Glass
Mix in a spray bottle:
1 quart warm water
1/4 cup white distilled vinegar or 2 tablespoons lemon juice
Use both vinegar and lemon if you want the cleaning abilities of vinegar with the scent of lemons.
Windows
Mix in a spray bottle:
1 quart of warm water
1/4 cup white distilled vinegar (use apple cider vinegar for a more pleasant scent) or 2 tablespoons of lemon juice
Use as you would any window cleaner.
Tips: A squeegee is a great tool for cleaning windows. A razor blade is handy for scraping off dirt or paint before cleaning.