(His) grandmother’s trick: Wash with a net
My grandmother, who was very chic, collected cashmere jackets.
He gave me some, with very good advice: before putting the cardigan in the washing machine, wrap the buttons tightly in aluminum foil. Wash the vests very frequently because the more you wash them, the softer and more beautiful they become. Wash them only in cold or lukewarm water, or at 30°C. And above all, above all, put them in a net, like lingerie.