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You’ll need high-quality images that communicate your concept. This image uses fractal brushes to create the impression of light and dark auras around the birds. To deepen and vary colour, use brushes with different hue blend modes. The Liquify filter helps to give the auras the impression of motion. For the starfield, fill a layer with black and go to Filter>Noise>Add Noise, setting Amount to 130%. Apply Layer>New Adjustment Layer>Levels and slide the left handle to the right to deepen the shadows.
Paste your images, such as these birds, into the composition and desaturate them (Image>Adjustments>Hue/Saturation). Use a Curves adjustment to boost contrast and Blur filters to soften layers. Using a large, fuzzy brush, add colour by painting with a variety of hues in Overlay, Colour, Multiply and Soft Light. Now hit Select>All, Edit>Copy Merged and Edit>Paste. Apply a Gaussian Blur filter with Radius: 80px, set to Soft Light at 40% Opacity. Turn the layer on and off to see the difference a glow can make!