What do you do if the shoe fits??

I've been giving a lot of thought to the phrases we use lately.  I received one of those "Life in 1500's" emails that gave the explanation and origin of some familiar sayings. (i.e. It's Raining Cats and Dogs, Throwing the baby out with the bathwater, Peas porridge hot Peas porridge cold...., etc).  When I looked them up on snopes.com I found that nearly all of them (all but one) were untrue.

So while I'm still unsure of where most of our slang comes from, I have found myself questioning our language.

While driving today I saw a license plate cover that said
"If the shoe fits..."

hmmmm, ok.

If the shoe fits....what?
    
Maybe you can help me.  This is what I have come up with so far:

If the shoe fits-
      then it must be yours!

      then it's the right size.

      buy it!

      it's on the correct foot!

     

That's all I came up with.  What about you? What do YOU do when the shoe fits?? :D