"The rate of change of momentum is proportional to the imposed force and goes in the direction of the force."- Sir Isaac Newton, 1687
Newton had the right idea. Please note that the force must be properly directed, not mis-directed. Seek quality, rather than quantity.
1. First, choose the right hammer for the job.
That would be Thai Language Course, 5th Edition. It won't do any harm to try a variety of learning materials. Use whatever works for you. I don't know of anything more effective than Thai Language Course, 5th Edition.
2. Next, start with a few gentle taps on the nail. If it bends or goes in a little crooked, you must pull that nail out and start all over again.
This means that you learn to speak Thai by starting with a single tone. Start with a single syllable, applying its correct tone. Listen to it a few times, then try to repeat it with exactly the same pitch as the Thai speaker. If you are not sure that your tone is correct, try a different word that uses the same tone. This will help your brain to absorb the tone, rather than vowel or consonant sounds.
3. When you begin hammering the nail, do it slowly. Do not hit it too hard, because you might bend the nail.
It won't help you to shout, scream, or repeat the tone incorrectly. Can't get it right? Ok, fine. Deliberately try to say the syllable with the wrong tone! (This might help you to hear the difference.) Got it wrong? Good. Now fix it! Make it right. Frustrated? Confused? You should be. You are attempting to smash your way through the Thai tone barrier, which requires practice. So, take a break. Try it again later.
4. On impact, the face of the hammer must be centered precisely on the nail head. Keep your eye on the nail.
As you practice, you may benefit by looking at the transliterated tone mark or at a graphic representation of the tone. Those who are learning to write may focus on the Thai script. In either case, you must pronounce the tone exactly right. This might take you five minutes, or it might take you 20 years. Some people can easily hear their own pitch, others find it difficult. Practice listening to your own tone. Over time, you will get better at hearing yourself. If you are not able to hear your own tone, you will have to find a Thai person who is willing and able to correct you. Good luck with that – very difficult to find!
5. Hammer the nail directly on the head in a continuous fluid motion.
When you are pretty sure you've got the nail set right, Drill baby drill! Say it again and again, with that single syllable and its correct tone. Got it right? Ok. Try another tone. Now, practice the pair. Compare and contrast the tones. (Chapter 1 of Thai Language Course has lots of these exercises – with both audio and video.) Soon you will be ready to put some syllables and words together.
6. Let the weight of the hammer and the momentum of the swing drive the nail, not the force of the blow.
This only happens after lots of practice – words just flow out of your mouth, without you having to give them much thought. This is the product of drilling tones. Now, you are speaking Thai.