Mark it out with Rectangular Marquee Tool and make a copy of it: Edit –Copy (ctrl+c) . Get back to the girl's window and insert the picture in a new layer: Edit – Paste (ctrl+v). Select the Crop Tool to increase the dimensions of the picture and correct the background's placement: Edit – Free Transform (ctrl+t).

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Create now a new layer, under the girl's one and select a standard brush (Brush Tool) of "star" shape and big size to insert a dot behind the girl.

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Make it look fluffier by copying the layer (сtrl+j) and flipping it vertically: Edit – Transform – Flip Vertical. We also may increase a little the "star"'s sizes: (ctrl+t).

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Merge down these layers: Layer – Merge Down (ctrl+e) and blur out the new layer by applying the next options: Filter – Blur – Radial Blur.

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Make the "star" look yellow, using the next command: Image – Adjustments – Hue/Saturation (ctrl+u).

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Make the necessary corrections on the background's colors: Image – Adjustments – Selective Color.

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Change after that the layer's Blending Mode, containing the "star" on Overlay.

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