Caring for your delicates is well, a delicate matter. We suggest hand-washing your Thistle & Spire. We know it's a drag, but high-end laces last the longest when handled with care.
1. Dab any stains with mild soap and water and gently rub. (Hook your bra/bodysuit together to keep it from catching or tangling)
2. Soak for a few minutes in the sink working suds gently into the fabric and rinse thoroughly.
3. Press against a towel to remove excess water.
4. Lay flat to dry (Remember, don't ever put your intimates in the dryer! The heat breaks down the elastic and spandex, making them fall apart sooner.)
For more details check out Refinery 29's how-to article.