Step 4 On a new layer, create a rectangle with a colourful gradient. Duplicate it a few times at different sizes and filled with gradients of different colours (above left).
Create a series of variations using Edit > Transform > Warp. Go crazy and make some weird abstract shapes. Now place the shapes over the highlights on your image and change the blending mode to Screen.
Step 5 To bring out areas such as the arms that may be difficult to make out, we’re going to add some lines with the Pencil tool (B). Set the Size to around 19px, and ensure that ‘Simulate pressure’ is on if you’re using a tablet. Draw black lines on dark areas and white lines on light areas.