What is a one-sentence summary of the following article?
Archivists and conservator-restorers are professionals who specialize in preserving historical artifacts, including paper. They should be able to flatten and preserve all paper materials at a high quality, including watercolors, old or fragile paper, and other objects that can be difficult to safely flatten at home. Search online for document archival services in your area, or ask a librarian for hep finding one. As mentioned in the other methods, wetting the paper, or "humidifying" it, can help remove wrinkles caused by torn and displaced fibers. Archivists often use special tools and extreme care to increase the humidity of the paper significantly. If you are brave, and have a few test pieces of paper to try out first, you can try to mimic some of these at home before pressing your paper. One of the easiest might be the "Horton Humidifier" method. Place the rolled-up paper in a plastic cup, open to the air. Place the cup in a plastic garbage can, add water to the bottom of the can, and close the garbage can lid. This can cause mold growth on the paper, which is difficult to treat at home. Some archivists use anti-fungal chemicals such as thymol or ortho-phenyl phenol, but these materials can be highly dangerous to the user and the paper if used incorrectly. One archivist's tool is widely available for commercial sale. Purchase archival-quality plastic envelopes to keep your important documents, family history, and other papers safe for decades if not centuries, protecting them from moisture and ultraviolet light.

Summary:
Take valuable documents to a professional. Learn about humidifying techniques. Store materials in a preservation envelope.