Use a meat tenderizer to pound any thick parts of the chicken thigh so that they are as close to uniform thickness as possible.
Sprinkle the garlic herb seasoning on the meat side of the chicken thighs and the salt on the skin side.
Place chicken thighs, skin side up, in a single layer in your air fryer. Cook at 400 degrees F for about 18 minutes. Skin should be golden brown and very crispy. Internal temperature should read at least 165 degrees F when done.