What do I need to bring to the immigration office to extend my 60-day visa exemption in Thailand?

To extend your visa exemption in Thailand for an additional 30 days, you will need to bring your passport (along with photocopies), a completed TM30 residence form, cash (around 1900-2000 baht), and possibly a departure flight ticket and recent photos (usually two). It's advisable to arrive early at the immigration office for quicker service.