Clean before close inspection
Dirt and body oils can hide thinning and make handling unpleasant. Follow the garment care instructions and let it dry fully before marking or placing a patch.
If washing could worsen the damage, support the weak area temporarily and use a gentle method. Do not create a larger hole simply to follow a general rule.
Check shrinkage and colour
Compare measurements before and after washing, especially around seams and the intended patch. Colour transfer from denim or a printed cloth can affect the thread palette.
Wash the patch fabric in a compatible way when possible. Matching preparation reduces puckering when the two textiles later share the same care routine.
Repair at the working state
Lay the clean, relaxed garment flat and mark the area in the position it will normally have. Avoid stretching it to make a hole look smaller or more regular.
After stitching, wash a sample or follow the established care plan and inspect the repair again. The process is complete when the garment remains useful, not merely when the thread ends are hidden.