This is a very simple technique with an amazing number of possibilities based on the brush you choose and blend mode you use. In this example, we’ll use a photo on an angle, but of course this method will work for any photo. (In case you want to try it on a rotated photo, I’ll cover those steps first. If you don’t want your photo to be rotated then, well, don’t rotate it!)
Press Command-J (PC: Control-J) to duplicate the Background layer. Then use the ...