When I'm prctising of reference, I always try to search for interesting lighting, expression, environment or clothes.
Here what caught my eyes were the beautiful light effects on the face.
<<< Read more of the process.
Scroll down for step by step pictures ♥.
The sketch of the basic shapes
Basic skin tone.
Darker mid-tones added.
Darkest shadows.
Highlighted areas
Fixing shapes and adding more values for depth.
Adding a little shine ♥, because I really like shine, and she has make up on.
Carefully working further on rendering the picture to the finest, while avoiding the mistake to lose the definition of the shapes.
Giving some extra shadow on the edge of the picture, to help the eye focus on the center of the picture.
Adding some colors to her face, 'cuz it makes the focus point more vivid and happy.
So good to be a digital artist, I like retouching the colors.
Reference used, picture is from Fenty Beauty site.