Superimpose is a broad term and describes the wide variety of effects a designer or photographer can use to combine, combine and edit images.
You can create an illusion by superimposing elements on an image or hide something in the original image. So, whether you're placing an updated logo on a product photo or putting images together to create a collage, overlaying images is an important photo editing technique to understand.
How to superimpose images;
1. Organize your images in Photoshop
2. Remove the background
3. Adjust the mask
4. Add blur to the background
5. Turn it into a Smart Object
6. Make the final adjustments