Click Image ---> Adjustments ---> Treshold. sposta a little cursor to increase/decrease visibility.
Click on your background image on the panel on the right and instead of normal choose screen,lighten o similar.
Before te do that, te need to unlock background layer. You're going to do that da double clicking little lock on the background layer. Then add textures.
In this Elena photo, I used a link link postato to this spot.