The best way to correct an overly salty dish is to dilute the salt flavor. Kitchen Daily notes that salt can't be removed, but it is possible to bring it into balance with the dish's other flavors.
The easiest way to reduce a salty flavor is to dilute it by adding more ingredients to the dish. Add water or salt-free broth to soups, sauces and gravies, and stir in additional meat or vegetables, if necessary.
According to Food52, salty is one of five tastes. The others are sweet, sour, bitter and umami, or savory. Balancing the salt with additional sweet flavors, such as sugar or honey, or a sour one, such as lemon juice, may be an acceptable method of masking a dish's saltiness.