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Once your old photographs are clean, store them in a protected area that is also dry. You can, for example, put them in an envelope and store them in a drawer in your home that is not prone to moisture or humidity. This should keep your photos in good shape after the cleaning process. If your photos are very old, consider professional storage. You can check online to find companies in your area that provide specialized storage for old, valuable photographs. The quicker you clean out stains, the better. If you spill anything on an old photograph, or get dirt on it with your fingers, clean it promptly to prevent the stains from becoming set. Stains can quickly be removed by running photographs under tap water or placing them in a pan of water briefly. Swish the photograph around to remove any stains. Handling old photographs infrequently will protect them from damage. Old photographs are fragile, so it's important not to over handle them. Only handle photographs when absolutely necessary, such as when you're moving. For the most part, keep them in storage to preserve them over time. It can help to have digital copies of your photographs. This way, if you want to look at old photographs, you can do so on screen to avoid handling them.
Store your photographs in a dry environment. Remove new stains quickly. Minimize how often you handle old photographs.