The best advice they can give you is get yourself a good Lawyer. You should also get the names, addresses, and telephone numbers of every witness pertaining to your case. Many cases have been lost simply because the defendant could not locate a witness. Also write down the times and dates of the events surrounding your case, this information can be easily forgotten, and sometimes desperately needed to win your case. Once you get all the information together, contact a Lawyer and discuss your case.
Timing is very important.
You cannot contact a Lawyer too soon. In some cases, the sooner you contact a Lawyer, the more they can help. Don't assume that because you think you are guilty, a Lawyer cannot help. People who are innocent need to be defended. People who are guilty need to be represented.