To repair a scratched leather sofa, the materials you need to prepare include: sofa repair glue, hooks, and acne needles.

1. First squeeze out an appropriate amount of repair glue and set it aside for later use.

2. Then use a hook to hook up the sofa leather, and use the round end of the acne needle to spread the sofa leather.

3. Then use a pimple needle to dip an appropriate amount of sofa repair glue and apply it on the inner layer of the sofa leather.

4. After applying, use a hook to gently press the sofa leather. This will allow the glue to bond more closely to the sofa leather.

5. Let it sit for a while and wait for the glue to dry completely, so that the scratched leather sofa will be repaired.