Legal Question in Criminal Law in California

It is not up to an individual to "press" or "drop" charges. That decision is completely up to the prosecutor's office.

The prosecutor's office may take your wishes into consideration when deciding to file a case or to dismiss or plead it. You can let them know any way you choose. There is no magic form. Some prosecutor's offices do have a form that is particular to that county, but you'd have to check with them.