First you file a PAGA claim online with the California Labor and Workforce Development Agency (LWDA) and have it served on your employer via certified mail. (PAGA filings cost $75, though you may be able to get this waived.) The LWDA will then decide within 65 days whether to take the case. If they do not, you are free to file a regulation lawsuit. Either way, you are advised to consult with an experienced California labor law attorney first to discuss your options.