Silk Dupioni

For laundry: to maintain its crisp original appearance simply cold water wash and hang to dry. Use a warm iron to remove any wrinkles.
If you choose a darker colour silk, sometimes the colours will bleed onto lace if you wash the garment as above so you might consider dry cleaning. Be sure to test if you are consider washing by hand.
You can machine wash and dry but this method changes the texture, softening it considerably. Be sure to test a piece before using this method to see if you like the result.