Read What to Do After the Court Decides Your Small Claims Case (Form SC-200-INFO).
If you did not go to the trial for a good reason, you can ask the court to vacate (cancel) your judgment (called a "default judgment") and give you a new trial date. You will need to file a form called Notice of Motion to Vacate Judgment and Declaration (Small Claims) (Form SC-135).
If you lost and owe money, pay the court or the other side (the plaintiff). If you do not pay, you must mail a form called Judgment Debtor's Statement of Assets (Small Claims) (Form SC-133) to the plaintiff within 30 days. After you pay, make sure the plaintiff files a form called Acknowledgment of Satisfaction of Judgment (Form SC-290 or Form EJ-100). If the plaintiff does not file this form, you can ask the court clerk to enter a "satisfaction of judgment" if you can prove you paid the full amount of the judgment with the interest and costs.
After you ask the plaintiff in writing to file the Acknowledgment of Satisfaction of Judgment (Form SC-290 or Form EJ-100), he or she has 14 days to comply. If he or she fails or refuses to comply, you can sue the plaintiff for $50 plus any actual damages you incurred. To read about the law, see California Code of Civil Procedure section 116.850.
If you won after filing a Defendant's Claim and the other side owes you money, try to get them to pay you. Once they have paid, file an Acknowledgment of Satisfaction of Judgment (Form SC-290 or Form EJ-100).