start with seeing if your nail catches on it - as stated above.
if not, start with a fine polish, and work your way more corse, using a finishing pad - till its removed and then back to fine again.
if it catches, use a cutting pad and a corse polish, working your way fine, this will remove some of it. then get it touched up.
OR
you confident to take wet / dry to it?
do the above and then wash the area, what ever is left, spray 1000grit and lightly, very lightly rub over the top of it. every 2/3 rubs, wipe it down with a wet cloth, flip the paper, spray it and go again, until its gone.
then polish it with a finishing pad to bring it back up.
IF its down do the actual base coat or deeper, i.e to the panel, similar principles apply but more work needed.