How do I reuse fabric from old clothes?

Treat a garment as a collection of small flat panels rather than as fabric. The limit is almost always size: a shirt back gives you one decent rectangle, and everything else is offcuts.

Wash it first, before you cut and before it comes anywhere near your fabric store. Anything already shrunk and softened is stable, which is one advantage over new fabric.

Judge the wear honestly. Hold the fabric up to the light. Thin patches, pale worn zones and sun-faded shoulders will fail soon after you sew them, and a garment made from tired fabric is a wasted afternoon. Discard those areas rather than working around them optimistically.

Cut it open rather than unpicking it, in most cases. Cut just outside the seams and you lose a centimetre; unpicking a whole shirt costs an evening and returns needle holes along every edge. Unpick only when you need the maximum width.

Find the grain again. Old seams and hems are not reliable straight lines. Locate the grain by pulling a thread or following the weave, and re-establish it before laying pattern pieces.

What suits reclaimed panels. Children’s clothes, pockets, bag linings, cushion covers, bias binding, patchwork, facings and interfacing test pieces.

Other good sources. Bed linen gives large flat pieces of soft cotton. Curtains give heavy widths, though often sun-damaged along one edge.

Keep buttons, zips and elastic. Cut them off before the fabric goes anywhere.