1. Take the curtains down, if desired. Lay the curtains out onto a flat surface.
2. Vacuum off any dust or debris on the curtains with a hose attachment.
3. Mix 1 tsp. of dish-washing soap and 3 cups cool water. Stir.
4. Soak a sponge with the dish-washing mixture and wring out the majority of the liquid.
5. Dab at the stained areas of the curtains with the sponge. Avoid allowing too much water to come in contact with the velvet as this could cause damage.
6. Allow the curtains to dry thoroughly, which could take anywhere from 24 to 48 hours depending upon the thickness of the velvet.
7. Hang the curtains back in their original spot