This is never a good way to approach a situation in life, and you should refrain from doing it. Consider this as an alternative; ignore him. Do nothing. Do not react to him at all.
The simple truth is that if you do anything to get so-called revenge on him, you are basically telling him you can't handle being without him. He wins, you lose. The more you try and make him miserable, the more he knows he's still the center of your focus. You can't get him out of your head. He'll go to his friends and laugh and say things like "she can't live without me."
A strong person moves on. An intelligent person does not seek revenge. This just makes you look bad. And the more revenge you try to bring, the more satisfaction he'll get out of it all—because soon the new girl will want to defend him, and he'll get a big rise out of two girls fighting over HIM.
Just give it some thought. Think about it. Use your head. Outsmart him. That'll do wonders for you as well when you realize you are bigger than the loser you discovered him to be.