I performed a test to restore the original color (Simonis Tournament Blue) to burn marks in the cloth.
I used an art marker made by Prismcolor in it's "True Blue" color, #PM-39, available at any art supply store and certainly available online. There was another color marker which more closely matched Simonis Tournament Blue but my theory was that the burn-marked areas still had some color in them, so I'd go with a color one shade lighter. Seems to be the right amount.
The art marker pen:
The burn spot (before):
The burn spot immediately after applying color (NOTE: All you need to do is "dot" the mark; use the fine point and place a dot in the center and 5-6 dots midway between center and edge. DO NOT fill it in like you're filling in a machine-read test answer.)
Notice that it looks darker than the cloth; that's because it's wet. Take a paper towel and rub it around a little, wait a few hours and it will look like:
The original burn mark is about 1/4" to the right of the chalk cube but you'd never see it.
I'm sure they have markers for other color cloths. My only suggestion is to buy one that is one shade lighter than the perfect match.
I used an art marker made by Prismcolor in it's "True Blue" color, #PM-39, available at any art supply store and certainly available online. There was another color marker which more closely matched Simonis Tournament Blue but my theory was that the burn-marked areas still had some color in them, so I'd go with a color one shade lighter. Seems to be the right amount.
The art marker pen:

The burn spot (before):

The burn spot immediately after applying color (NOTE: All you need to do is "dot" the mark; use the fine point and place a dot in the center and 5-6 dots midway between center and edge. DO NOT fill it in like you're filling in a machine-read test answer.)

Notice that it looks darker than the cloth; that's because it's wet. Take a paper towel and rub it around a little, wait a few hours and it will look like:

The original burn mark is about 1/4" to the right of the chalk cube but you'd never see it.
I'm sure they have markers for other color cloths. My only suggestion is to buy one that is one shade lighter than the perfect match.