The best way to wash silk shirts is by first finding the detergents that are made special for silk clothes. Second, use your hands to wash the silk the first time you use a detergent. You should also follow the directions given on the detergent. Then, follow the instructions on http://www.ehow.com/how_4886562_wash-silk-shirt.html.
Dry clean is best. Of course if you are on a budget, use the dry cleaning sheets, such as woolite. Wal-Mart, local grocery, may even find it in the dollar store. I do most of my dry cleaning at home. As a seamstress, mom and grandma I'm very pleased.