It said, "Do you need a neck exercise? Look to your right." When he looked to his right, it said "look to your left". When he looked to his left, it just said to look at his right again.
I just can't remember the movie this scene was from. I think it was a feel-good movie. The guy was a wallflower or probably a drug dealer. I could be wrong though. I do remember him being in his teens. It's a teen movie.