How can I make him jealous?

Date his friend, it works all the time but make sure you don't hurt the friends feeling find a cute friend so you can date him for a while with out getting board.

Don't think about him. Work on looking your best. And having fun. If you go into a plan to make him jealous it could backfire and you end up feeling worse. What if he acts like he doesn't care. Then you will ponder what is he feeling or you will hurt all over again. It is not worth your time or effort. I would go somewhere else that he won't be! Make he wonder where you are. Remember, less can be more! Missing you is way better then jealousy! Best of Luck to you!

Why is it so important to you to make him jealous? The only way he is going to regret braking up with you is if he had some real feelings for you and if he dumped you for no reason I've got to say he does not have much for real feelings for you. The best thing you can do is look as good as you possibly can every time you see him. Have as much fun as you possibly can enjoy your life as much as you can and move on. Maybe you'll fine a man who can appreciate you.

Get with one of his friends! hahaha! Seriously, that would do the trick. And he would be miserable seeing you happy with a friend of his.