How do you learn to read lips?

Its something that takes a long time to master, you just have to kind of teach yourself.

To learn how to read lips, when someone is talking keep a good eye on their lips while they talk (if they feel comfortable with you doing so) and practice by asking them to lip talk you a message (with no sound) to see if you can read their lips.

You get familiar with how people's lips move when they say certain Words or phrases.