We have to represent the background now. Make visible firstly the background's layer, clicking on the eye's icon near it in the Layers window and merge down the rest of the layers: Layer – Merge Visible (shift+ctrl+e). Then make visible again the background's layer and paint it in a different color if that is necessary, applying the Paint Bucket Tool. Next we have to apply the Rectangular Tool to represent the frame for the picture:

Miu Miu Anime Girl

Make a copy of the girl's layer and make the lowest copy looking entirely white, selecting the next option: Image – Adjustments – Channel Mixer.

Miu Miu Anime Girl
 


Enlarge a little the layer, selecting the next option: Edit – Free Transform (ctrl+t) and click on the next buttons: alt+shift.

Miu Miu Anime Girl

Select the Gradient Tool to illuminate one of the background's corners:

Miu Miu Anime Girl

Next we have to make a copy of the background's layer and apply to this copy the next filter's option: Filter – Sketch – Halftone Pattern.

Miu Miu Anime Girl