In order for a defensive back to be effective, it all starts with a proper stance.
A low comfortable stance begins with proper flexion. Sink your hips, bend your knees and keep some flexion in your ankles. Your chest should be over your knees with a flat back, head up.
Stagger your feet based on which side of the ball you are playing. The closest foot to the ball, which will be your inside foot, should be closer to the line of scrimmage, while your outside foot is staggered back, ready to backpedal. Your arms should be bent at the elbow at a 90-degree angle, ready to engage the receiver. You should feel strong and balanced in this position.
Master the proper stance through repetition. First, work on stepping into and out of the stance, repeating this motion to get the feel of the proper stance. Ask a coach to watch you get in and out of your stance to help with proper positioning.
Once you can consistently get into the proper stance, you can expand on this drill by working to backpedal three strides. Again, ask your coach or a teammate to check that you are staying in a low, athletic position during this backpedal, rather than standing tall.
Now that you have your stance down, it’s time to learn the fundamentals of pass coverage.