Lesson 6 of the Beginner's Photoshop course I'm doing was all about textures, and showed how to use a photo with a texture as a background for another photo. It was easier than I'd expected! I'd deliberately chosen a very strong background so I could see the effects more easily. And I got my layer mask to work first time, which is something I've struggled with in the past.
This is something I'm going to have fun with.