I don't really recommend traveling by bus in here. Roads are dangerous, especially if a many hours journey is involved. Said so, taking a flight to a very near place, like less than one hour flight, would be better.
I wish I could be a perpetual tourist, but nah. I have to work 8 hours a day from M to F and even some weekends. Said, so I wrote "Others, remote work". And yes, I understand that some other people are on a workcation mode/freelancer mode. In my case it's just a regular full-time job for a regular company, with fixed hours, so choosing Tourism would be inaccurate at best.
The outbound flight information isn't a mandatory field. You can leave it bank.
As for purpose, choose Other: Living in Phuket (or whatever you want to write, you can write anything). Don't forget to write your visa number on the form.
In my last entry, which was the first after the introduction of the TDAC, I chose Other: Working remotely from Thailand. I'm on a DTV granted on a remote job basis.
ohhh, sorry. I now realized "TT" means Thai Tag 😅 In Korea we used TT (or ㅠ or ㅜㅜ if using the Korean keyboard) to express sadness, so I got confused. My bad.