We find the best way to clean a dab mat full of dabs is with alcohol. This is only good for silicon dab mats and not mouse pad type mats.
If you have a mouse pad type mat we feel one of the best was is the same as one might do for wax.
Put two paper towels over the top of the wax stain. Set an iron at a low to medium heat and iron over the area. The heated dabs will melt again, and come away from the fabric, soaking instead into the paper towel