Make a colorized Britney Spears effect in photoshop using different techniques and blending modes.

1.
I started out with a image of Britney Spears and cut out the background with the magic wand tool, then under that layer I created a background layer with a white color.

2.
Now start by making a copy of your Britney layer, I just renamed them 1 and 2.
With the top layer selected go to image -> adjustments -> desaturate to make the layer black and white.

3.
Set the black and white layers blending mode to hard light and then go to image -> adjustments -> levels and drag the handles like in the image below.

4.
Hide the black and white layer by clicking the eye next to the layer in the layers panel.
Now make a new empty layer and zoom in on one of the eyes, then grab your polygonal selection tool. click around the inner eye to get its selection, then hold down shift and press backspace and fill it with a default color.

5.
Then set its layer blending mode to overlay, and zoom in on the other eye, do the same procedure as before. Now i renamed the layer to eyes.

6.
Make a new layer, name it mouth and zoom in on Britney Spears mouth.

7.
Again with the polygonal selection tool click around the mouth to get the mouth selection, Then get click the selection mode, subtract from selection and click the inside mouth of Britney, so only her lips is selected, then fill it with a default color.

8.
Now set the mouth layers blending mode to overlay.
Go to filter -> blur -> gaussian blur and give in amount of about

9.
You can now change the eyes and mouth color by selecting it and go to image -> adjustments -> hue and saturations and drag the handles, try dragging them as i did in the images below.

9.
Make the black and white Britney Spears layer visible again by clicking where to get its eye visible again in the layers panel.

10.
Now while having the black and white layer selected make a mask layer, now you see a mask layer at the right side of the black and white britney layer, when you select the mask layer and paint with white, then you erase stuff, and paint with black then you bring things up. So hold down the ctrl key and click the eyes layer, to load the selection, then paint with black inside the eyes to bring forth the colors from the layer beneath. Do the same with the mouth layer.

11.
Then you are done, you can still go back and change the eyes and mouth color with image -> adjustments -> hue and saturations. (For the finished image I changed the mouth and eyes colors a bit).