What documents do I need to apply for a 90-day Thailand visa and when should I apply?

To apply for a 90-day Thailand visa, you'll need to check the specific document requirements from the Thai Embassy in your country, as these can vary. Generally, documents should be uploaded in PDF format. You don't need a booked flight, but you should provide flight information. It's recommended to apply around 2-3 weeks before your intended travel date, ideally about 2 months in advance if you plan to travel at the end of September.