Focus on the eyes. Sharp eyes are desirable in a portrait. Use the central focus point to lock focus on the model’s eye.
Use a standard lens this will help compress features and provide a natural looking result. Classic portrait focal lengths for a full-frame camera are 50mm, 85mm prime lenses and a 70-200mm zoom.
Aperture priority mode gives you a direct control with the aperture thus it can create a smooth, out of focus backgrounds.
Use natural light with a silver reflector to achieve a stunning portrait.