Covering the stain with a few spritzes of aerosol hair spray is the tried-and-true method! Get one with a high alcohol content (the first ingredient on the list) and treat the stain while it is still wet by dousing the spot. Let it dry and don't touch it or else you will embed the stain even more. Within minutes the alcohol will pull the ink to the surface, bubble up and dry. Then you can flake it off with the edge of a knife.
Image from WikiHow