Separate the pocket layers
Identify the pocket bag, opening, side seam and any topstitching. Insert a piece of card or a removable barrier inside the pocket so the repair does not join layers that must move independently.
Mark the worn area from both sides. A hole at the opening may need a different patch shape from thinning on the pocket face.
Reinforce the correct surface
Place the patch on the side that supports the damaged cloth and keeps the pocket usable. Baste the layers without trapping the pocket bag or changing the opening’s shape.
Choose an open pattern and moderate thread weight. Pocket fabric often needs to flex and accept objects, so avoid a dense, bulky field at the entry.
Test function before finishing
Put a hand and a small object in the pocket, then turn the jeans inside out to check for catches. Trim or secure loose edges before washing.
The final repair should feel smooth in use and strong at the stress point. If it blocks access, redesign the patch rather than hiding the problem with more stitches.