Assuming you are referring to cleaning stained glass, the following tips should help:
1. Fill a clean bucket with cool water and add a few drops of mild dish soap.
2. Using a soft sponge or cloth, gently wash the glass in a circular motion. Avoid scrubbing too hard, as this can damage the glass.
3. Rinse the glass with clean water and dry it with a soft, lint-free cloth.
4. If the glass is still dirty, repeat steps 2-3.
5. Once the glass is clean, apply a thin layer of glass sealant to help protect it from future stains.