Why
When shooting outdoors, sun is an excellent light source. However, we can’t change its brightness. You might decide to overexpose the sky to properly expose a subject’s face. Alternatively, you can turn the subject’s face towards sun, but then you must deal with squinty eyes. Further, sometimes, you go out to shoot and cloud gods decides to mess with you because they are bored, and you get an overcast day. For all such uncontrollable scenarios, flash is an outstanding tool.
How
The first step is to dial in an ambient/ environment exposure. Idea here is to properly expose your environment so that no part of it is blown out/overexposed.

In this picture, I exposed the environment so that details in the sky/background is visible (here, background trees behind the fog). Conversely, I could have properly exposed the subject, but then, all the details in the fog would have been lost.
Since we all love bokehlicious backgrounds, keep the aperture as wide as your lens allows (here, I set my aperture to f4, because f4 is the wide maximum aperture of my lens), and use shutter speed to control the exposure. Following the rule of thumb, set the shutter speed equal to or faster than your focal length when hand-holding your camera. Increase your ISO if environment gets too dark (refer to the post Exposure and More for detailed explanation).
Next, we add in the flash to expose the subject! Most of the times I stick to TTL when mixing flash and natural light. However, in darker environments, such as in the above picture, TTL tries to compensate for the overall scene and tend to overexpose the subject. In such cases, switch the flash to the manual mode and dial in the desired power; you should be able to nail the exposure in few tries. Keep the flash above the subject and in the general direction of the sun, to have natural looking pictures.

As you can see in the above picture, I have added the flash on the camera right 45 degrees to the subject. Also, I have kept the flash above the subject’s face and pointing down, brightening the ground a bit to give an impression of sun rays peaking from the clouds.
Final image

So next time you go out on a shoot, keep your flash handy, even if you are shooting at an ideal time when natural light is aplenty. You never know when you’ll need it.
Gear Used/Model
Gear: Canon EOS R with 24-105 F4 L Lens, Godox AD-100 Flash, and a human light stand 😊
Model: Ingried James
Very informative. Thank you for sharing
Welcome 🙂 much appreciated!
Very Nice. Thank you for sharing.
Welcome 🙂 much appreciated!
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