Immediately blot any spilled or splashed nail polish with a paper towel. Do not rub the nail polish; you will only spread it out and work it deeper into the grain.
Let the remaining nail polish dry overnight.
Dip a piece of 0000-grade stainless steel wood in furniture oil. Remove the excess oil by blotting the wool on a paper towel.
Gently sand the affected area with the steel wool to remove the remaining polish. The oil will help to protect the wood finish; apply more to the steel wool as needed. It will take some time to sand away the nail polish, but using more pressure will only damage the wood.
Wipe off any excess oil with a paper towel.
Repair any color damage caused by the steel wool with a touch-up pen in the color of the cypress, following the instructions on the pen.