- 1). Remove the cap and brush from the nail polish bottle. Plug the mouth of the bottle with wadded plastic wrap. Form a tight seal.
- 2). Soak one or more cotton balls with non-acetone nail polish remover. Clean the brush bristles, stem and the inside of the cap by swabbing them with the cotton balls. Allow all parts to dry thoroughly.
- 3). Glue the brush inside its cap using heavy-duty, waterproof glue, if the brush has detached. Allow the glue to dry for 24 hours before replacing the cap on the bottle.
- 4). Place a pinhead-size drop of glue on the folded end of the bristles, if the bristles have come out. Reinsert the glued end into the brush's hollow shaft. Allow the glue to dry for 24 hours. Trim any uneven bristles using sharp scissors.
- 5). Fix a brush that has broken in half by cutting off a 1/4-inch piece from the end of a round toothpick. Put a dab of glue on the blunt end of the toothpick and insert it part way into one end of the hollow brush stem. Allow it to dry for 30 minutes. Put a drop of glue on the sharp end of the toothpick and insert it into the brush's other half. Align the repair so that the stem is straight and let it dry for 24 hours.
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