Contact a probation officer.
Most counties have a probation officer who assists in sealing juvenile records. You may contact this officer by contacting the court. The probation officer will likely interview you. You must be honest during this interview and remember to emphasize the positive. Give them the information they require. The officer later will prepare a report to send to the court. NOTE: You must go through this process for each county you have a record in.
Attend the court hearing.
You will be notified of the date and time of the hearing. A district attorney may appear and argue against your request. Be prepared to provide proof of employment, school attendance, and anything else which may show the court that you are 'rehabilitated.' If you are intending to enlist in the United States military, you may wish to bring paperwork relative to that, or, better yet, a recruit officer to vouch for you. If your request is denied, you may reapply later. NOTE: Some judges require a period of 'good conduct' and may ask you to return in several months to see if you are still 'doing well.'