[header] How to clean a varnish brush [title] Clean your varnish brush immediately after using it. [step] Cleaning your varnish brush immediately after using it will prevent any buildup in the bristles, which can cause your brush to get stiff over time. Make it a habit to clean your brush every time you use it so it can stay in good condition. 
[title] Wear rubber gloves and work in a well-ventilated room. [step] Mineral spirits are a type of paint thinner useful for getting oil paints or varnishes out of brushes.