Deadlift Lat Engagement (Arm Against Ribs) Drill

This is a drill that emphasizes the use of the lats in the deadlift.

Stand in a neutral position with the ear, shoulder, hip, and knee in proper alignment. Have the arms rest comfortably at each side of the body. Begin to squeeze the shoulders against the body so that the lats become engaged and the shoulder girdle experiences depression and retraction. 

If this isn't enough, use a towel or another object and place it in the armpit. Begin to squeeze the object for a couple seconds on and a couple seconds off.