How can I effectively remove water stains from paper?

To effectively remove water stains from paper, gently blot the affected area with a clean, dry cloth to absorb excess moisture. Then, place the paper between two clean, dry towels and press with a heavy object to help absorb remaining moisture. Avoid using heat or rubbing the paper, as this can cause further damage. If the stain persists, consult a professional conservator for specialized treatment.