California has an abbreviated, summary proceeding for someone in your situation. You can get the forms on line along with the instructions on how to fill them out. Good luck.
You will first need to file for a Complaint or petition for legal separation (semantics different in different states), as you have already figured out, then you can amend to ask that you be granted a divorce instead. You will need to file a document that memorializes the agreement which you and your spouse have reached, and it typically has to be signed in front of a Notary Public and also may expire after a certain period of time if you don't follow through and file it with the Court. Ultimately, a final order granting a divorce will be entered and you will be divorced. Many jurisdictions have online forms that will help you handle this type of divore pro se (on your own without an attorney), but you might still consult with an attorney in your area to find out if there might be anything that you haven't thought of that could affect your decision on the property division. Also, some judges are very particular about the paperwork filed in their court, so there might be some subtle things you might miss that could actually hold up your divorce being granted, another good reason to consult with an attorney. Good luck!
I agree that you may qualify for a summary dissolution. http://www.courts.ca.gov/documents/fl810.pdf
When parties do not meet the residency requirements for a divorce - they can file a petition for legal separation and later amend it to divorce when in fact the residency requirements are met. (Hopefully, one of you now meets the requirement) So what you are trying to do is amend the divorce to a legal separation and then amend it back again for a divorce? If I recall correctly (and I'm not going to look it up for a free answer - you will have to verify for yourself or hire an attorney), you have unlimited time to amend the Petition until there is a Response. After the Response is filed you have 10 days without filing leave of the court. I noticed that some of the other answers addressed Summary Dissolution. Is this what you originally filed (based on less than 5 years from date of marriage to date of separation, neither own real estate, no significant assets or debts by either party? I don't remember exact numbers.) If this is what you originally filed - I have no experience. Please let me know what happens so I can advise other people.
B. Stuart Walker
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