Wash wool or cashmere by hand in Luke warm water, and never expose them to direct heat.
Fill a tub with lukewarm water and a few drops of mild detergent, dishwashing liquid will work. Immerse the sweater, and swish gently, Soak for 10 minutes.
Never wring or stretch wool when wet. it can be pulled out of shape dry flat .
Cashmere can be washed safely in a lingerie bag in gentle cycle, but they’ll last longer if washed by hand. Again flat dry.
After squeezing out water, lay the sweater on a white towel. Roll the towel with the sweater together to remove moisture, squeezing and pressing as you roll.
To get rid off sweater pills,
Remove the little balls, one pill at a time, using a small pair of scissors or a razor blade. There really isn’t any easier way. But your sweaters will look as good as new.