Attract the attention of the student before speaking with a cue such as a tap on the shoulder or wave.
Face the person while talking (try to avoid facing the chalkboard while speaking).
Speak clearly and naturally without exaggerating lip movements or volume.
Avoid standing in front of a light source like a window-- the glare from behind makes it difficult to read lips.
Do no chew gum, smoke, or otherwise obstruct the area around your mouth with your hands or other objects that interfere with speech reading. (Be aware that facial hair can inhibit speech reading).