White/yellow discharge coming from 6 week old breast reduction incision? (Photo)

It appears you have developed some wound dehiscence along your incision. This will usually heal well with some simple wound care. I recommend you contact your surgeon for specific instructions.

You might only need a couple of weeks of skin care and cream. For a definitive answer and management, you should contact your surgeon.Dr. Ted Eisenberg, Board Certified Plastic Surgeon and Author

Based solely on the photo, it looks like you have minimal amount of wound separation that appears to be almost healed.  You should ask your surgeon how he wishes you to take care of it.