As you prepare to block, pull your other arm back as you prepare to block, until it’s even with your floating ribs and ready to strike if needed. Also pull your hips back at a 45º angle, facing away from your forward foot and drawing your vitals farther out of reach from your opponent.
Once the student advances in a particular modality of training, then and only then
It may also be helpful to practice in front of a full-length mirror. Keep in mind that basic karate kata should be ambidextrous, allowing you to practice techniques on both sides equally.
