I'm going to show you how I use the templates that I created to create one of my covers. I'm also going to have a few of the templates that I've made so far I plan on making more in the future so tell me some sort of things you guys want. Thank you guys for being patient with me on my very long leave, but I intend on posting a lot more on here. 

This is the cover I'm recreating 

1) Open the template you want to use, I'm going to be using the octagon one for this

2) Use the magic wand tool and select an octagon and copy it (sorry you can't see it well) 

3) I pasted the octagon on the cover I'm making 

4) I started to arrange the octagons how I wanted them. To add more of the shape just copy and paste or you can also duplicate the shape 

5) Add whatever photo you want to use and set it to screen. You can resize it and rotate however you like until you get it in the desired place

6) If there is any of the image thats out of the template then you can use the eraser tool and erase it 

7) Now repeat the steps to the rest of the photos. Then add your title and any other finishing touches. 

TIP: It's easier to merge all of the layers together, excluding the title, because you can resize and move the whole finished template with the photos without having to move them individually. Also to give the photos a more unified look you can set your photos to black and white because the photos having different lightings and filters.