I have a wide and flat belly button. What can be done to make it as small as possible? (Photo)

Dear Humorous7970,
it is hard to tell for sure without an examination but based on your photo, it looks like you would be a good candidate for umbilicoplasty. If you are considering a surgery, I would suggest you to consult a board-certified plastic surgeon. Only after a thorough examination you will get more information and recommendations.
Daniel Barrett, MD

make sure the surgeon making all the promises will live up to what was 'guaranteed' and if not, then what?  Do you get complimentary revisions?  Or a partial refund?  Its very hard to make a belly button more narrow.  Deeper, yes.  Smaller in diameter?  Not so easy unless you are having an excision with reconstruction and that is done in separate stages.  Your belly button is really not bad so if you were in front of me, I would truly suggest nothing.

Requests for the esthetic reshaping of body parts are not to be separated from the person behind the request. The reason is that surgery is never an easy deal and comes with certain risks that might make the requester long for the original condition to be restored. In your specific case ANY surgery carries with it the risk of scarring and of altering your belly button to a shape that does not satisfy you. This risk has to be balanced against the WHY is it that the current shape of your umbilicus is bothering you? It takes an in-depth analysis of your motives to uncover this and perhaps preventing you from making a mistake you might regret. On the other hand, your request might be totally valid. Work needs to be done to answer your question. Best of luck.