Cry is signed by making a sad face and tracing imaginary tears down your face using your index fingers. Start with your index finger extended, just below your eye, and move the index finger down your face. Alternate with the opposite index finger on the other side of the face. Move your index fingers up and down your cheeks in alternating motions, making your face look unhappy and projecting real emotion so that your baby understands the meaning.
The sign cry can be used to label the emotion when your baby or someone else is crying. Being able to label the emotion and sharing it with you can reduce your baby's crying and avoid contagion when someone nearby is crying. "Julia is crying. Why don't we go and try to cheer her up?"
Try to use this sign to encourage your baby to communicate instead of cry. We like to teach this sign using videos of babies crying.