Adding a set of initials or some other kind of identification mark to a golf ball can be a good idea when it comes to recognizing your balls at the range. But sometimes the problem becomes removing those marks.
Opt for a standard soap-and-water solution when trying to get your golf balls clean. Since this method is easy and free, there's really no reason not to try it first.
Use an acetone-based nail polish remover if the marks on the golf ball are from a permanent marker. This method often has positive results.
Try a lacquer thinner to eliminate marker remains on a golf ball.
Run the balls through the dishwasher or washing machine to remove the marks. Make sure before doing this, however, that the exteriors of the balls are not cracked or punctured at all.
Clean the balls in one of the many golf ball and club cleaning apparatuses on the market. Or try a specialty cleaning solution designed specifically for golf balls.
Soak the balls in a diluted bleach solution. Do not leave them in for too long, though, since this could potentially dehydrate the surface of the balls.