Getting nail polish out of clothes is beating me

Let it dry completely first, wet polish just spreads. Scrape off what you can with a blunt knife. Then test acetone remover on an inside seam before going near the stain - acetone dissolves acetate and some other synthetics outright, it doesn't just lift the polish. If the fabric's fine, lay the stain face down on kitchen roll and dab the back with remover on a cotton bud, moving to a clean bit of roll as the colour comes through. Non-acetone remover is slower but safer on anything delicate. Normal wash after.