Go through the letters of the alphabet and make the sounds of each letter together with the adult you are teaching. This might sound simple, but many times, the adults you teach are learning English for the first time and may not be familiar with the English alphabet.
Make the sounds that occur when certain letters are grouped together. These are the sounds that become different when letters are put together, as opposed to when they are apart, such as the "sh" sound, the "ch" sound and the "gh" sound.
Add written materials to your lessons. Once you go through the sounds, start incorporating syllables that come together to create sound. For example, to reinforce the "f" sound, you can use syllables like "dif" and "fan." Remember to include grouped sounds like "ch."
Focus more closely on sounds that your adult learner seems to have trouble with at this point. For example, some people who are learning English may have trouble with the sounds made in English words that are not common in their primary language. Go through these sounds with your student again and ask that he make the sounds with you.
Start using words and phrases in your phonetics lessons with your adult learner. Once your adult student can comfortably make the sounds, you can add words. Using the syllables introduced above, you can create words like "different" and "fantastic." Then, put the words into phrases, such as "fantastic that we all are different."