Rule #1 You need to learn the Thai script. This includes the consonant classes,the tone marks and how to work out all the rules. If you don’t do this you won’t ever be able to pronounce anything properly. By mastering this entire system, learning Thai becomes much easier. Skipping this part will cause you mountains of frustration.
Rule #2 You should try to read a little every day. It will be painful sometimes in the beginning so just start by trying to read a little bit every day. Even one sentence is better than nothing. Just be sure and read it more than once, especially if it’s short.
Do whatever you can handle and there is no need to do it in one sitting. Spread it out over the day. Most days read stuff that you are already interested in. Now and then, read other stuff just for variety or because you happened to encounter it somewhere.
Rule #3 Listen everyday, as much as possible. Anything that is real language. We want to keep away from manufactured teaching materials as much as possible.
That stuff rarely resembles real language.
Rule #4 REVIEW things you want to remember. Occasionally you’ll see something once and it will stick forever, but most things will require some form of repetition and or real usage in a social situation to embed itself forever in your mind.
Consider using an SRS (Spaced Repetition System). This is just a fancy name for FLASHCARDS that have a built-in algorithm which makes studying more efficient by showing you cards that you are bad at more often than ones you are good at.
Rule #5 Carry a small notepad and write it in all the time. Sometimes you will hear a word a few times, but it hasn’t clicked yet. Write it down and find out what it is. If you are speaking the language and you want to say something that you don’t know yet, write it down and find out how to say it later. Next time you want to say that particular phrase/sentence, it will be in your pocket. We don’t have much control over what we remember and what we don’t so write it down! *Bonus – Keep track of your expenses/meals/daily activities/exercise in the language. You will quickly get good at spelling the things that you do everyday.