Extending the life of the clothes you already own is the single most effective thing an individual can do about textile waste. It also saves money, which is the more persuasive argument most of the time.
1. Wash less often
Most clothing is washed before it needs to be. Jumpers, hoodies and jeans can usually be aired instead. Every cycle causes mechanical wear, so halving the number of washes does more for a garment's lifespan than any other single change.
The exceptions are anything worn against the skin all day and anything actually dirty.
2. Stop tumble drying
Dryer lint is your clothing, in powder form. Heat and tumbling break fibres, crack prints and cause most shrinkage. Air drying takes longer and costs nothing.
3. Wash cooler and fuller
30°C cleans effectively with modern detergent. A full drum reduces the number of cycles. Both are free.
4. Repair early
A loose seam takes two minutes at the start and is unfixable once the fabric has frayed around it. Learn to sew a seam and replace a button — that is the whole skill set, and it covers most garment failures.
5. Store properly
Fold knitwear and heavy tops rather than hanging them; hangers stretch shoulders permanently. Give things room to breathe. Make sure everything is clean before long storage, since body oils attract moths.
6. Buy for the wardrobe you have
The garment most likely to last is the one you actually reach for. A piece that only works with one other item gets worn rarely and eventually gets given away in good condition — which is waste of a quieter kind.
When it really is finished
Textile recycling banks and charity shops take more than people think, including damaged items, which get sold on as rags rather than binned. Very little needs to go in general waste.
Our side of it
Fabric weights and compositions are listed under Materials on every product page, so you can judge durability before buying. Care specifics in caring for printed t-shirts and washing a hoodie. On materials, see organic cotton explained.
Further reading: WRAP: Textiles