Focus Objects in Photoshop (Colored with Black And White)

In many cases, you want to focus an object in your photo; you could achieve this using many techniques with the help of Photoshop. Here is a technique that achieves this by merging colored with black and whiteareas in an artisticway.

Open the photo in Photoshop.
Press (Ctrl+J) to duplicate the Background layer and rename it to "BW".
With the "BW" layer selected, press (Shift+Ctrl+U) or click Image > Adjustments > Desaturate. Now you should see two layers: Black and white layer "BW" and a colored layer "Background".
Press (Q) to "Edit in Quick Mask Mode" then press (B) to select the Brush tool.
Make sure that the "BW" layer is selected, set black as the foreground color and paint over the object that you want to focus (the girl in this photo).
After you have finished, press (Q) again to "Edit in Standard Mode".
Press (Shift+Ctrl+I) to "Inverse Selection", now you should see the object that you want to focus is selected.
Press Delete and if you want to colorize other simple parts, press (E) to select the Eraser tool and erase those parts.
Make sure the "BW" layer is selected, click Filter > Artistic > Colored Pencil and press Ok.
Select the Background layer, click "Create new fill or adjustment layer" > Levels, move the white arrow to the left a little to give the focused colored objects more brightness and press OK.