So you are here, you are not queer and you are ready to explore. Before they let you in, the first thing you need to do is to go through Thailand's immigration line. But even prior to that, you need to do some filling in--not your tooth but that innocuous arrival/departure card. You're sitting in your seat, minding your own business (or in reality shitting your pants because you know, the only thing separating you from Thailand and its eventual sexual escapade, is that mere 30 minutes) when all of the sudden the flight attendants start handing out these cards to the passengers.
You are told to fill them in but apparently, some people are so dense and absent-minded that they leave this very simple task until they get to the immigration booth and what happens then? The officer sends them all of the way back to the long, long, loooong freaking line that they'd endured waiting for hours, tip toeing after some exhausting double-digit-hour flight. So here's the look at the  Only the registered members can see the link. Register here.
Just to make sure you get the message here, at the immigration desk, they will not allow you to fill in the form on the spot. It would be wise, for the sake of yourself and everyone else, to fill them out before being called to the desk. It is also important to remember that for the duration of your stay in Thailand, the TM number would be required at many hotels to register you. And if you lose it? Good luck spending a few hours before your departure dealing with the proper paperworks. It is noteworthy,  Only the registered members can see the link. Register here.
, to make sure you also fill in the departure card as well.
There might be some ambiguities on some of the items. If you have a dual nationality, choose the country that you are arriving from with the correspondent passport. Of course, the visa number should have been stamped on your passport so it's right there. The address of residency can be filled in later or if you are staying at several locations during your stay, put the first one. You got on the right plane to get here so I would assume you do have the flight number. Don't fudge the TM number (left hand side corner).
On the new "arrival" form (since 2005), you also have to indicate your yearly income (don't ask me what this one is for--there are many speculations so I just leave it there), purpose of visit (i.e. pedophilia, drug trafficking, etc... I kid), type of accommodation and flight, whether this is your first trip, your occupation, from/port of embarkation, and disembarkation. This information is important for the Thai Immigration Bureau to track down and avoid visitors with different intentions for visiting the Kingdom of Thailand.
Welcome to Thailand.