When performing seated cable rows you have a choice of a number of different bar attachments. Personally I like the "V" bar and the straight bar. The "V" bar attachment really only has the one grip you can use. If you decide to use a straight bar make sure you use a shoulder width grip.
Sit in position with your knees slightly bent. Pull the bar to the bottom of your sternum and thrust your chest forward to give an extra stretch at the top of the movement. At the top of the movement do not lean back more than 15 degrees. As you let the weight back down to the starting position, bend at the waste and stretch your lats at the bottom of the movement.
Keep your elbows close to your body throughout the entire movement and make sure you are not jerking the weight through the exercise. Repeat the process.