Turn the jeans inside out
Trim loose threads around the rip
Cut a denim patch slightly larger than the tear
Place the patch behind the rip
Pin or clip the patch in place
Sew around the tear with a needle and thread or a sewing machine
Use a zigzag stitch or straight stitch to secure the edges
Reinforce the area with extra stitching if needed
Trim excess patch material
Turn the jeans right side out
Press the repaired area with an iron