Mark it out with Rectangular Marquee Tool, make a copy of it: Edit –Copy (ctrl+c) and get back to the girl's window to insert the background on a new layer: Edit – Paste (ctrl+v). Move then this layer lower than the girl's layer and make the necessary corrections on it, selecting next option: Edit – Free Transform (ctrl+t).

portrait of beautiful girl

Now we should change the background's colors for them to look harmonious on the picture. It's possible to do this operation, selecting Image – Adjustments – Selective Color.

portrait of beautiful girl

Get back to the girl's layer to introduce more flares on her hair using the Dodge Tool.

portrait of beautiful girl

Apply after, turn by turn, two filter on this layer: Filter – Distort – Diffuse Glow and Filter – Brush Strokes – Sprayer Strokes.

portrait of beautiful girl 

portrait of beautiful girl

Make a copy of the background's layer (ctrl+j) and place the copy upper than the girl's
 
layer. Create out of this layer a mask: Layer – Add Layer Mask – Reveal All and select the Gradient Tool of black color to make visible only this part of the layer, situated on the bottom.

portrait of beautiful girl

Change the gradient's color on white and make visible now this layer on its upper part.

portrait of beautiful girl

Merge down all the layers: Layer – Merge Visible (shift+ctrl+e). Then make a copy f the new represented layer (ctrl+j). It should be processed with the filters too: Filter – Brush Strokes – Angled Strokes.

portrait of beautiful girl

Select the Layer Mask to make this layer visible only along the picture's edges. We should do that as for the background not to get out on the front plan.

portrait of beautiful girl

Merge down the layers now and dark out the picture's edges, applying the Burn Tool.

portrait of beautiful girl

Start making the final corrections on the brightness and on the contrast (ctrl+m).

portrait of beautiful girl