Here are some hints and fundamentals of defensive back play.
•Always know your opponent. Know the types of routes that they like to run and know what formations they like to run them from.
•Know how to adjust to spread sets and other formations quickly.
•At all times know who you are covering or what your coverage responsibilities are.
•The first few steps are critical to good coverage. When a defensive back looses a battle with a receiver it is almost always in the first three steps of the route.
•Rarely if ever will a coach want you to line up head up with the receiver.
•In your stance put your outside foot forward.
•Bend your knees for good balance and to keep your center of gravity low.
•At the snap push off hard with the front foot. Work on this with your backpedal drills.
•Know your key and keep your eyes where they need to be.
•Stay low in your backpedal.
•Keep your feet close together but never get them crossed.
•Lean forward in your backpedal.
•Turn your foot when you go to plant it for a break.
•Never let a receiver break your cushion. This allows him to separate on a break.
•When the ball is in the air it belongs to you.
•Try to intercept the ball or deflect it at it's highest point. This denies the receiver the ball. Be careful here not to misjudge and give the receiver the ball behind you.
•Once you pick the ball tuck it quickly, yell Oscie ( or what ever your team uses for a pick), and return the ball to the nearest sideline. This gets you away from the main body of the defense. There are less possible tacklers on the sideline.

As a defensive back you are required to do an enormous amount for you team. You have a hard and complex job. With more and more attack style defenses being used you will be in situations where no one is covering your back. Many times the defensive back is the last line of defense. If a nose guard misses a tackle the linebacker will probably cover for him. If you miss a tackle there is a good chance the opponents back will be playing their fight song. You must be a good cover man as well as an excellent tackler to play defensive back.

Remember, nothing turns a games momentum faster than a picked pass for a touchdown. Be aggressive and always be willing to do extra work to make yourself better.
Defensive Back Play