Removing shiny skin, greasy face and forehead

1. Open the image which has shiny skin. We are only going to reduce the sheen, not eliminate it completely or the image will look unnatural. We have to keep the overall luminance and contrast to match the rest of the image.
2. 
3. Create a new layer (Shift+Ctrl+N) on PC or (Shift+Command+N) on Mac and give an appropriate name. This is where we will perform our grease reduction as so not to modify the original image.
4. 
5. Reduce the opacity of this layer to 51%. This can be changed later on depending on how much of an effect is required.
6. Press B to select the Brush tool. Set the size of this brush so it is roughly a quarter of the height of the shiny spot. E.g. you would have to brush across 4 times to completely cover the area. You can experiment with this but I have found this method to work for me.
   
7. We are now going to sample an area of forehead very close to where the top of the shine is. Hold down the Alt (PC) or Option (Mac) key and your cursor turns into a dropper tool. Click the area of the skin next to the shine. Your selected colour will have changed to this skin colour.
8. Click and drag a line across the top of the shiny area. you should now have something like this.
9. 
10. Hold the Alt/Option key again and sample an area of skin on the next line down.
11. Repeat this until the entire area is covered. You should now have something like this.
12. 
13. I increased the opacity of the layer to 62% which seemed to work ideal for this image.