Don't have a beard or a face covering. (This can be tricky with some cultures requiring a face to be covered.)
Don't have a bright window behind you (which will silhouette your head and make it harder to see your mouth.)
Don't have a bright window behind you (which will silhouette your head and make it harder to see your mouth.)
When I've had conversations with people who lip read I've made sure to keep my speech at a reasonable pace, avoiding talking too quickly, and I tend to sharpen up my pronunciation and annunciation to avoid slurring words or letters.