I have about 50 pages worth of information on this subject. The point being that it is too much for me to post and I would be violating the Copyright Act in doing so. Moreover, I would be doing you a disservice by trying to give you a narrow answer, because you may find that your approach is wrong, once you study the appropriate materials.
I suggest that you visit your county law library and read CEB Publications, Practice under the Family Code (2009), Chapter 18: "Attack on Judgment in the Trial Court."
You can also purchase the above practice guide online here (but it ain't cheap). Here is an exerpt from Chapter 18 on moving for a new trial:
When a party believes that his or her substantial rights have been materially affected at trial, for causes defined in CCP §§657-657.1, a new trial may be requested. Code of Civil Procedure §656 defines a new trial as "a re-examination of an issue of fact in the same court after a trial and decision." It is now well settled that issues of law, as well as fact, may be the subject of a motion for new trial. See CCP §657; Marriage of Beilock (1978) 81 CA3d 713, 720, 146 CR 675. The request for a new trial must be brought before the same judge who presided at the original trial, unless he or she is unable to hear the matter. Strict time requirements apply to all filings in the motion for new trial procedure; if the requirements are not met, the right to request a new trial is lost.