Use a normal warm to cool machine wash cycle with wool wash or a regular PH Neutral powdered or liquid detergent, just find one without whiteners, brighteners, stain removers or enzymes. Detergents which have 'Don't use on wool or silk' in the small print contain a nasty wool eating, skin irritating enzyme called protease. Separate lights and darks as usual.
Drying
Dry flat in shade to best preserve shape and colour. You can dry on the line, but expect some twisting of the garment and seams. As with any garment, inside out and out of excessive sun will help prolong the depth of colour.