You may want to pound the chicken breast to get it to an even thickness.
Make sure you flip the chicken over midway during the cooking time to get it evenly cooked on both sides.
Avoid overcrowding the Air Fryer basket. I would ideally stick to 1-2 chicken breasts at a time, depending on how large the chicken breasts and your Air Fryer basket are.
If you have a large chicken breast but you're short on time, you can chop up the chicken into medium chunks and then air fry them. This will cut down the cooking time.
Always let the chicken rest for a few minutes before you shred it, but make sure you shred it while it is still warm.