Just did my first 90 day report in Bangkok and wanted to share in case it helps anyone, since there were some confusing parts I wish I had known about. Took me 2 tries.
I'm on DTV visa and first attempted to do the report online, which was rejected since the first 90 day report needs to be in person.
I showed up at the Immigration Division 1 building (Gate 2) at about 5:45am. There was an orderly line in rows and you just get in the shortest row, which is the end of the longer line. Not long after 6am, they let us in and gave us each a paper with a number indicating our place in line. I was around the 100th person each day, which I found was plenty good (no reason to come much earlier than I did). After I got the number, there is a very quick passport check and security screen similar to an airport entry. Then you can enter the building and walk around freely. There is a table near the immigration office entry with forms and officials that are helping people get the right forms they need, but if you are prepared, you won't need that. So, now you have a couple of hours to just wait, which is actually not bad since there are several coffee shops on the floor below and some vendors in the main hall with food, etc.
IMPORTANT: Around 8:15am you need to go sit in your assigned chair. This is only for the first 200 people I think (if you arrive later, then it's probably different). Basically, near where you entered, along the wall near the immigration, there are very long lines of chairs with numbers on them. Find the chair with the number of your ticket and sit there till they start bringing people in. They will do this in order of your ticket number, so be sure to stick with the people near you and keep going to the front even if people with higher numbers get confused and go in front of you. They only let you in by order of ticket, so stick to the order.
CRITICAL: Be VERY clear about what you are there to do. This is where I failed the first day. I relied on the officials to direct me. They are doing their best to move fast and will send you to the wrong place if you are not VERY CLEAR. The first day they sent me to get a tourist visa extension. I was too inexperienced to know better. The next day I corrected my mistake and made it VERY CLEAR I was there for 90 day extension. This is a different line than the 3 main lines for your next queue ticket (for me it was line 4 I believe). Line 4 is specifically for 90 day reporting queue tickets. They will give you a ticket - for me it was A1 and 029 - where A1 are the 90 day reporting processing windows and 029 was my number in line. Follow the signs to that section and wait till your number is called.
Obviously, my second attempt went much better than the first! The official that processed me never once spoke a word, just took my papers, did some stuff, then handed me the document stating I had reported.
As far as documents I took, it was these:
* Passport
* TM47 (2)
* DTV visa (2)
* Photocopy of Passport photo page (2)
* Photocopy of Passport entry stamp (2)
* TM30 (2)
The only thing the official kept and used was one copy of the TM47. The rest she just handed back to me without hardly looking at them. So, it appears I may have come overprepared, but I would much rather overdo it than underdo it.
IMPORTANT: On the first day I came, one of the officials examined my documents and told me they only accept actual "original" photocopies of the various passport pages. Meaning that you cannot just take a picture of your passport pages, then print those out (unless you are highly skilled at making it look EXACTLY like a photocopy). Just get photocopies - super cheap and easy to do.
Overall, it went much smoother than I expected. I lived in Romania before this and it was a month of prep and tons of documents and stress. This was a breeze in comparison. The flow of people is well organized. My main failure initially was not being clear enough about why I was there and expecting them to take the time to fully understand my situation. They are doing their best and trying to move as quickly as possible, so you need to be super clear and pay attention to where they are sending you.
As far as transport, I took a Grab there and that early in the morning traffic is not an issue. Drop off and pickup at Gate 2 is pretty easy. This is the main gate from what I can tell, so you shouldn't have to do anything special to have the driver drop you there. For getting home, I'd recommend taking a Grab to "National Telecom" monorail station on the Pink Line which you can then take to connect to the MRT/BTS network since the traffic may be rough when you are leaving. If you have a Rabbit card, it will work for that. I don't recommend walking to the station since there is quite a bit of construction in the area and you might have to walk in the road with traffic in some sections, which would not be fun.
Like I said, overall was not too bad, and hopefully this helps anyone doing it for the first time!
(I rarely check FB, so forgive me if I don't respond to questions right away, but I'm sure others will)
