Shooting natural light portraits does not mean you are stuck using the sunlight exactly as it is without any modification. You can use modifiers to shape the sunlight to be more flattering, and this great video tutorial will show you an effective way to create such illumination.
Natural Light
A Modern Approach to Film Photography With Flash

Of course, flash photography existed long before the transition to digital. However, most modern film photography is shot in natural light, whether out of an aesthetic desire or because working with flash and film is a bit of a lost art. Nonetheless, just like digital, flash can open up a lot of creative possibilities, and this excellent video tutorial will show you a modern approach to doing so.
A Beginner’s Guide to Working With Speedlights for Portrait Photography

Learning how to work with artificial lighting is something every portrait photographer should learn, as it will free you of relying on certain locations, weather, and times of day and enable creative shots that would not be possible otherwise. If you would like to start learning, check out this fantastic video tutorial that will guide you through the process of lighting a portrait using a combination of a speedlight and natural light.
See How Peter Hurley Uses Natural and Continuous Light for Headshots

Most professional headshot photographers use strobes for their studio work, but of course, that does not mean you can’t use continuous or even natural light for your work. This excellent video tutorial from the one and only Peter Hurley will show you how to use both natural light and continuous lighting for taking headshots.
3 Subtle and Natural Off-Camera Flash Portrait Techniques

Photographers who are new to working with artificial light often think that strobes always look distinctly different from natural light. And while it is true that you can shoot creative, highly stylized images that would not be possible with just sunlight, you can use strobes to emulate natural light to make subtle, natural looks. This excellent video tutorial will show you three off-camera flash lighting techniques that will allow you to create effective and compelling portraits.
Off-Camera Flash for Beginners

You can do quite a lot with natural light, but if you want to truly take full control of your photos, learning how to work with artificial light is the way to go. If you are wondering how to get started, this excellent video tutorial will guide you through the process of shooting outdoor portraits using a speedlight and affordable shoot-through umbrella.