The sign for yell as in "scream," or "call out to."
Hold a loose "C" hand, palm up, near your mouth (sort of as if you were holding an apple which you were about to take a bite out of) and then move your hand forward and upward as if representing a "yell" coming out of your mouth. Match your facial expression to the intensity of your yell.
YELL / "call out"
Notes: