Familiarize yourself with the alphabet. Use a chart with the Thai alphabet and phonetic Latin equivalents to recognize the pronunciation of the letters. Because there is no standard for translating the sound of Thai letters to Latin letters, write the sounds as they make sense to you. Listen to a native speaker pronouncing Thai to make sure you are correctly pronouncing the letters and tones.
Practice writing the script. Start with the letters and work your way up to words. Flashcards are helpful for memorizing the alphabet, but you must practice writing as well. When you can write the alphabet from memory with the markers for the tones, start to string the letters into words.
Practice pronunciation. Thai can be a challenge for those not familiar with tonal languages. With tonal languages, the meaning of a word changes with the rising or falling of the voice. English speakers use tones for context (i.e., the voice goes up at the end of a question). Thai has tones that change the meaning of a word when you pronounce it with a different tone.
There are five tones. To practice tones in Thai, exaggerate them as you pronounce words. Listen to native speakers and repeat what you hear. This will help make the specific tones more obvious, and you will be able to distinguish words from one another more easily. The Thai alphabet includes markers to indicate tones, so you can tell which tone to use as you read the words.
Practice reading and writing the script. Listen to Thai as you read. Start simple, with words and sentences that you understand, or you will lose interest in the sentence and words and will not learn them as quickly.
Find something related to Thai that you are interested in and practice reading and writing about this subject. Thailand has art, religion, drama, dance, tourism attractions and food that are all highly distinctive and draws millions of tourists each year to the country. You will more easily learn the language if you are reading and interacting with subjects that interest you.