What are the requirements for extending a 30-day visa exemption in Chiang Mai?

To extend a 30-day visa exemption in Chiang Mai, you need to complete the TM 7 application form and submit a passport-sized photo along with copies of your passport's ID page, the visa exempt stamp, and your departure card. Additionally, if you are staying at a private residence, you must provide a copy of your notification of stay, or if staying in a hotel, a hotel receipt is required.