Unlike cotton or synthetics, silk is one of the most luxurious fabrics. It is also very difficult to wash safely. Theoretically, the best way to wash it is dry cleaning which is rather expensive! However, there are also some methods to clean it at home, without having to take it to dry cleaners.
First, soak the silk clothes in lukewarm water with a mild soap for about five minutes. Remember – the temperature is important in this case. Too cold of too hot water can stretch or shrink the garment. Then gently rub all the stains under the soap-water, often flushing and repeating the action. Don't rub too hard – it may damage the soft fabric. When you see that contaminants have been removed, rinse it with cold water containing 1/4 cup of vinegar. This will help to remove the soap and keep the silk garments fresh and shining. Finally you can rinse it once again with cold water alone to remove the vinegar smell.
After washing very gently wring the water excess out by spreading the fabric out on a towel and rolling it up and down. Newer twist the silk garments! The towel will slowly absorb the water. Just leave the garment on the towel and let it dry. Drying it in the machine dryer is usually very risky idea.
One more thing about cleaning silk – if your clothes are very colorful, you should check color fastness first by treating hidden part of clothing with soap (or any other detergent you plan to use for washing). If color transfers easily, you should better try a professional dry cleaning.