Rotate the trail elbow in toward the ball, not into the body
The speaker clarifies a common misconception: getting the trail elbow "in" does not mean pulling it into the body. "In" means rotating the elbow in toward the golf ball. Their cue in the set position is to point the funny bone or the ulna down toward the ball. He says this puts the club on plane and keeps the hands in front of the center of the body.
Channel: PorzakGolf
Watch official source at 4:05