Quick tip: Protect your photos
First, store photos in a cool, dry location such as a climate-controlled unit. You should never store photos facing each other because this can cause the photos to transfer on to each other ruining both of them.
Next, know that decaying photos emit chemicals that can cause good photos to begin breaking down as well, so if some of your photos are already decaying, store them separately from good photos.
Lastly, make sure you use acid free materials. Acidity in paper, cardboard, and some plastics can cause damage to photos. Instead buy acid-free albums which you can find at most craft stores.