CS Violin Polish For String Instruments helps polish string instruments.
Tip: start with one small section at a time, not a large section of the entire back, for example. More than a few players, even seasoned professionals, create quite a mess by trying to clean too large an area at a time. Whenever using a new brand of cleaner or polish for the first time, be sure to test it on a small, inconspicuous spot. Place a small amount of polish on a clean, folded cotton or microfiber cloth or clean soft folded paper towel. Using moderate pressure, rub polish onto varnish in a circular motion in 1" or larger circles. Wipe off excess polish before it has dried with another clean soft cloth or soft paper towel. Use light to moderate pressure either in a circular motion or in the direction of the grain.