Here’s a tutorial by photographer Stephen Davies on how you can create a pseudo double exposure photograph using a couple simple steps in Photoshop.
Step 1: Open It Up
Open up your background image in Photoshop.
Step 2: Overlay the Portrait
Open up your portrait and overlay your it on your background image.
Step 3: Blend Mode
Set the blend mode of the portrait layer to “Lighten”. Adjust the image to your liking.
Step 4: Crop and Flatten
Crop out the portrait and flatten the layers. Voila! You’re done.
Image credits: Photographs by Stephen Davies and used with permission