Select a brush of grass shape from the standard set of brushes and two different green nuances to insert the grass along the lowest edge of the wallpapers.

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Make it darker a little with Image – Adjustments – Hue/Saturation (ctrl+u).

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Decolorize the grass' upper part on a new layer, using the usual Gradient Tool.

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Change the layer's Blending Mode on Soft Light.

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Then we have to create a new layer under the sun's layer and set the next shown Gradient Tool's adjustments, selecting the colors of the stripes by pressing Randomize button.

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Create a kind of stretching, coming from the sun's central part and then make the layer look totally white with the Channel Mixer option.

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Minimize after that the quantity of the stripes and represent one more new layer to paint it out under a different angle this time.

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