Remove the drapes from the hanger and immerse them in a sink full of warm water. If the drapes are a light color, you can just immerse the part with the paint; bright- or dark-colored silk should be immersed entirely to avoid water stains.
Soak the drapes for at least an hour, then add a small amount of laundry detergent and use your fingers to gently rub away the paint.
Blot the affected area with a soft, white towel to remove any remaining paint residue.
Drain the sink and hang the drapes to dry, then press and reinstall them.
Remove the drapes from the hanger and flex the paint spot to make it crack. Dry acrylic paint is not flexible and should crack easily.
Gently lift away the pieces of paint with your fingers; peel any large pieces away from the fabric.
Brush the dry silk with a soft toothbrush to remove any small pieces of paint that remain.
Blot the affected area with warm water to lift away any remaining paint residue. If the paint has deposited color onto the drapes, hand-wash them in warm water with laundry detergent then hang them up to dry. Once dried, press and reinstall them.