I've seen some of the lip syncing videos and I'm amazed at how precise the flaps are to fit the lyrics of the song. So my question was, how exactly do people edit the footage to so precisely match the sylible of the word?
I mean the actual footage is going to be wording something totally different and big mistery to me. I have seen people mention that they use markers for each sylible, but still... how would you make the flaps fit the sylible?

