Fill a basin with lukewarm water, and add a mild detergent. Baby shampoo works well, or choose a detergent made for hand-washing. Swirl the detergent in the water to mix.
Immerse your shawl in the basin of water and detergent. Gently move it back and forth, to work the suds through the fibers. Allow the shawl to soak for 5 minutes.
Drain the water from the basin. Squeeze soapy water from the shawl, but do not wring. Refill the basin with cool water and swish the shawl around to rinse the fibers. Repeat this step until the water is clear.
Squeeze excess water from the shawl. Do not wring. Wringing stretches and distorts the fibers, and could cause stitches to break.
Place the wet shawl on a dry bath towel. Roll the shawl up in the towel, and then squeeze to express as much water as possible. For a large, heavy shawl, you may need to repeat this with a second towel.
Spread a dry towel on a table or counter. Arrange the shawl on the towel, laying it out flat and straight. Allow it to air-dry.