First gather and fill out the necessary forms. Make several copies and then bring the originals to the court with your filing fee.
After you have filed, you need to let your spouse know that you have filed. To do this, you have to arrange for them to be served with a copy of the complaint that you filed, “notice” and a “domestic relations summons”. These are papers that tell your spouse what has happened and what will happen next. The court will give you the notice and summons when you file your papers, but you need to arrange to have the papers “served.” See Service of Process for more information.
To get an annulment, you must be able to prove to the judge that one of the reasons above applies to your marriage. It is not enough to just say you both want an annulment. Judges will look very carefully at the specific reasons that an annulment can be granted. In some ways, this makes an annulment more difficult to get than a divorce.