"Luke... you must go to the Dagobah-system..."
Ever wanted to create those cool StarWars-ghost sightings? Well, just open up any picture to put the ghost on;
I will use Obi-Wan having a conversation with his old master Qui-Gon, now I need to open a picture of Qui-Gon first;
Then I need to cut the background out of it with a desired tool...
And cut off everything that doesn't fit the image.
You can see it clearly when you lower the opacity;
Ok, now you're done right?;
Now you can either add a Gradient Map or just duplicate (Ctrl+J) the layer 2 times and make both blue and set the top-layer to overlay;
Also add a white-blue outer glow;
Now lower the opacity to a decent amount;
And finally, if needed, press Ctrl+U to make the image a bit more lighter..