Keeping your bed linen in top condition is a matter of a few habits. Not complicated, not heavy, but consistent.
One. Read the washing instructions. Not all fabrics endure the same. Linen takes higher heat than satin. Cotton asks its own attention. What the label says usually holds true.
Two. Do not use too much detergent. Washing is mostly done by water, the detergent accelerates the process. Too much leaves residues that stiffen the fabric and irritate the skin.
Three. Wash bed linen separately. Not together with towels or coarser textiles. No zips, no buttons from clothes that catch in the fabric.
Four. Close zips or buttons of the duvet cover before washing. That prevents them from catching in other fabric.
Five. Low to medium temperature. Forty degrees suffices for most fabrics. Sixty only if you wish to dispel dust mites, and the fabric can take it.
Six. Do not dry too hot. High temperatures shrink the linen and speed wear. A moderate drying temperature suffices.
Seven. Iron while the linen is still slightly damp. Crisper, quicker, with less effort.
For the duvet itself, that is another matter. It belongs in a specialist atelier such as ours, not in a household setup.