Please, I Need Help with Giving Credit Where It’s Due? (Images)

I want to post an image in my post.

Then I want to say, “By John Doe.”

How can I make the “John Doe” part a blue link (It seems to keep disappearing on me) under the image?

I want to link it to “John Doe’s” page to give him credit for his image.

I have seen this done before in other sites, but I don’t know how I can do it?

Can you help me out?