There are several types of gloss to use over wood stain. Traditional gloss is clear and provides a protective layer over the wood. Varnish and shellac fall under this category. Tinted gloss can add a hint of color to the wood, which is beneficial for antique-style wood finishes. Some glosses come with a wood stain included, so that you add the color and the protection in one single application, which speeds up the entire process.
Applying gloss over stain is not difficult. First you must make sure the stain is dry. Wipe the surface of the wood with a dry cloth to remove any dirt or dust from the surface of the wood. The surface must be clean before applying the gloss. Brush the gloss onto the surface with a paintbrush just as if you were painting. Apply the gloss in the same direction as the grain of the wood for best results. Allow the gloss to dry and apply two or three coats of gloss.
Different glosses can make different effects on the wood. Semi-gloss will give the wood a dull appearance. Colored glosses will give the wood a different tint and color. If you use a combination of paint and gloss, you can create the distressed or worn look that is used in shabby chic styles of decorating. The highest shine glosses will create a formal appearance on the wood. Natural glosses, such as linseed oil, will produce a warmer appearance than synthetic glosses, such as polyurethane.
All glosses will protect the wood to some degree. However, some glosses are more effective than others. Natural glosses will eventually wear down and have to be replaced. Synthetic glosses will have a longer life. Some glosses yellow over time, while others retain their clear coloring. Check the label of the gloss before applying it to ensure it fits with your needs.