Practice controlling your throat muscles. Tighten and loosen the muscles as you sing various vowel sounds until you feel comfortable.
Try to make sounds in your throat without actually using your mouth. This helps you to feel how tight the throat needs to be.
Practice changing the shape of the lips, jaw and tongue to produce different sounds.
Allow sounds to form only when exhaling. Use your stomach muscles to control how much sound and the type of sound.
Inhale quickly between sounds. Don’t make any noise when you inhale. You should be able to resume the exact same sound when you begin to exhale.
Listen to other throat singers. See the Resources section below for links to sound samples. Practice the techniques above to imitate and even create your own distinct sounds.