Using the same person take between four and six photographs using different light.
The days have been consistently grey lately so artificial light will have to be used to meet the brief.
The first portrait (below) was taken in the morning using light from a large window on the model's right side (left looking at the photo) I have used a reflector to reduce the shadows on the other side of her face.
The second image was taken the same day but this time I have a tungsten lamp on the model's right side. A mixture of tungsten and ambient daylight has given a warmer feel to the image. I have adjusted slightly in photoshop. When I took this portrait tungsten white balance was too blue and daylight was too yellow. I opted for daylight and adjusted in the raw file.
A couple of days later this was taken in the afternoon. A very grey flat day so I used the yellow wall to add some warmth to the picture. I took a couple of images just before this one next to a grey wall it was very blue and flat. A very useful bit of knowledge gained here that a coloured wall can be used to reflect some colour back into a picture.
We were still having grey days so for the next image I have used flash and a gold reflector as my light source. To remove any distractions I have used a black backdrop. I think this portrait would have benefited from a little bit of rim lighting around her hair.
On the morning my model was leaving town we finally had a bit of sunshine and a bit of blue sky so en route to the train station I stopped her in front of the brick wall, the sunlight is shining on her face. I have used a small white reflector to bounce back a little light to reduce the shadows under her chin.
This is my favourite of all the images.