The back page of the Norweigan Sweater tells us how to look after our woollens. My own personal experience has been shrinking things, then learning handwashing and wishing that they still manufactured mangles as a pure wool jumper gets pretty heavy after it’s been dunked. I have to make do with rolling woollens in a towel and then deal with shed loads of sopping wet towels as I don’t own a tumble dryer.
Emu may recommend Dreft, but I recommend two products. Firstly Soak, which is a bit hard to find in the UK, but I get mine from a local quilting shop. It is also stocked in many yarn shops. You don’t have to rinse the Soak from woollens, so after a soak in the bath, you can go straight to the drying stage. I recently found a new shop and a new product. In 2020 Islington got a new store called Know The Origin which seems to exclusively sell environmentally friendly or ethically made things. I could have gone a little further and got the Soak, but the shop that sells it has steps and I was using my wheelchair, so I bought The Clothes Doctor No. 3 for cashmere and wool. Highly recommend!