No pads, no problem. Here's a drill.

TAG DRILL

PURPOSE

Emphasizes closing the distance, aiming point, pad level, and bending towards the quarterback in pass rush. It teaches the defensive line how to rush, half their man and stay on an edge. 

EQUIPMENT

Four cones and four tennis balls

SET UP

Establish a Line of Scrimmage, or LOS, as a starting point for the defenders. Place each cone four yards behind the LOS. Place each towel or tennis ball slightly behind and to the right of each cone. Each player will line up at the LOS to the left of each cone. Another player will line up as an offensive lineman opposite the defender. 

EXECUTION

On the coach’s command, the offensive player will kick step or back pedal towards the cone as fast as he can. The defender must get off with low pad level and beat the blocker to the cone. The defender must be able to dip his right shoulder and pick up the towel or tennis ball behind the cone. 

COACHING POINT

• Stage #1: Just use cones and balls, no blocker. 
• Stage #2: Cones, balls, blockers.
• Stage #3: Just blockers going straight back.