How do I file a petition for dissolution of marriage?

In CA you must file the following forms to start a divorce:

FL-100

FL-110

FL-105 (if there are children)

Then you have to have someone over 18, other than yourself, personally serve the above documents (along with some blank forms like a blank FL-120 and blank FL-105) and file proof of that service on the appropriate form. 

Filing just starts the process!  Filing does not make you divorced!

In addition, if you want the court to make specific orders (Custody, support, etc.) then you need to file a request for order, which is FL-300.  If you file and served an FL-300, then there are some other blank forms you need to serve on the other spouse as well (including the FL-320).

You should at least have a free consultation with a local family law attorney to get a better idea of what your case looks like and whether or not you need an attorney.

In Minnesota there are multiple ways to commence (to begin, to initiate) a divorce. 'Filing' means to deliver a document to the proper court officer where the document is then accepted and kept as a matter of record and reference.  Some divorces are quite peaceable and certain others may be quite contentious (much in dispute, much disagreement).  Minnesota favors peaceable means of dispute resolution in many, but not all, situations:  Examples are the FENE/SENE process and mediation. In divorces with deep and entrenched dispute, an attorney may say 'Sometimes it is best that the judge decide (the issues)'.  Divorces are often commenced by personal service.  Sometimes the whereabouts of one spouse is not known to the other spouse (who is seeking a divorce) so'alternative means' of attempting to notify the person may be made.  Oftentimes the full terms of a divorce may be reached entirely 'out of court' and then ultimately submitted to the court.  Oftentimes the divorcing husband and wife may agree in full to all terms for the divorce.  In my view, if you are contemplating divorce or know that you want a divorce, or, if you are concerned that your spouse may be considering divorce, it is always prudent and wise to confer with an attorney who practices family law and divorce.  I recommend you make several phone calls to attorneys in choosing the attorney you want to help you, because it is very important that you feel a sense of great trust and safety in the attorney-client relationship.

If you choose not to hire an attoreny, and for a simple divorce you don't really have to, you can file yourself. ere is a link to the state court system; it will provide you with the basics, plus the step-by-step procedure:

http://www.courts.ca.gov/selfhelp-divorce.htm