The first thing to do is go to court immediately and have any Warrant for your arrest recalled immediately. The longer you wait, the worse it gets. Most judges will allow you one "bite of the apple" and let you slide the first time you miss a court date. If you can't afford an attorney, one will be assigned to represent you. Make sure to have someone available who can post bail for you if the judge sets bail on you. Last, but not least, at least speak to an attorney from the Public Defender's office to see if they know the Judge or what else they can do to assist you.
The first thing you should do is call the bailiff for the Judge assigned to hear your case. Explain the situation and arrange a time to reschedule the court date. If the court date was for an arraignment, the bailiff will most likely have you come in for a walk-in arraignment at which time the warrant will most likely be recalled if one was issued. It is very important to contact the court immediately. Chances are the Judge will admonish you briefly for missing the date and then give you a personal recognizance bond which means that you will not have to post any money. However, it would be smart to have somebody at the arraignment just in case the judge sets a cash bond. You should also request a public defender if you are unable to afford counsel.