Step 11 Duplicate the Lines group, calling the new version ‘Lines Blur’. Alt-click on Lines Blur and select Merge Layers to flatten its contents. Then go to Filters > Blur > Gaussian Blur. Set the blur to 8px. This should give those lines a nice glow. Bump the opacity back up to 90%.

Step 12 Create a new layer called ‘White’ in the ‘Highlights’ group. As in Step 4, use the Gradient tool to add some white-to-transparent radial gradients to both ends of the lines we just made, and to the model’s right eye. Set the blending mode to Overlay and the opacity to 70%.

Step 13 Now change the colours of the Gradient tool to black-to-transparent and use some radial gradients to add shading to darker areas. This will add more depth to the overall piece. Try to concentrate on the eyes, hair and mouth to bring out details. You can even add a third layer to add some red in the same way.