File a notice of appeal. Within 90 days of the judge entering judgment in your unlawful detainer case, or within 30 days of receiving a copy of the judgment (whichever is sooner), you must file a notice of appeal. If the case is for less than $25,000 use Form APP-102. If the case is for more than $25,000 you must use Form APP-002, and the deadline to file the notice is extended.
Serve process. After you file the notice of appeal, you must serve the notice on the other party in the case as if it were a court summons. Typically, this involves hiring a private process-server.
Designate record. Within 10 days of filing your notice of appeal, you must also tell the court which documents and records (such as court transcripts) from the case you want included in the appeal. This is done through a notice designating record on appeal form, available from the court.
Move for a stay of enforcement or relief from forfeiture. If you were the tenant in the eviction case and you lost, you might have been ordered to vacate the premises. But you might be able to stay put, pending the appeal, if you would suffer a compelling hardship if forced to move. If that is the situation, file a motion in the court that entered the judgment, requesting a stay of enforcement or relief from forfeiture, and state your reasons.
File an appellate brief in the Court of Appeal. The appeal itself will be decided in the California Court of Appeal for your local district. Following the rules of appellate procedure for the court, you must file a timely brief stating the reason for your appeal. The opposing party will file a reply brief, and you might be called upon to provide an oral argument supporting your case.