With this tutorial I'm going to let you in on one of my secret techniques.
Why not? This is one of my favourite times of the year.
Step 1: Selecting The Photo
As you can see, it doesn't really matter about the darkness of the photo as you can fix this, all you need is a creepy pose would be excellent or even a blank pose works great. Head and shoulders works best as you can get up close and personal and see details such as they eyes (we will get onto that).
In my photo, I really opened my eyes so that the effect will really pop.
Step 2: Correcting The Photo
Adjust the middle notch until the image is lightened as high as it can go without pixelating the image. Then adjust the notch furthest to the right to get the highlights correct, and finally the notch furthest to the left ever so slightly so that you can enhance the shadows a little.
(Oh no! The horrible image is revealed. Seriously, this picture is not nice!)
duplicate the layer to be safe! (In the layers bar, right click on the "background image" and select "duplicate layer)
I always think the image works better with a blacked out background, but this part is up to you. Sometimes if the background is too light the black background won't work.
To do this: select a feathered and fairly large brush (for my image it's about 176 pixels.) When going closer to the head you'll want to use a smaller brush size and perhaps change the opacity in case anything goes wrong.