I cant show you because my photoshop isnt working but this is what you do.
1. Have your image opened already.
2. Create a blank layer
3. Hide the image layer by clicking on the little eye next to it on the layers.
4. With the blank layer, select the
Polygonal Lasso Tool5. With that tool, make the shape you want. For example, for your shattered glass, just make the shape by clicking and you can form whatever shape you want.
6. After you made your shape, right click it and there should be a option to make a selection out of it.
7. Make your image layer visible again by clicking on the eye again.
8. Press Ctrl+T for free transform and drag one of the edge corners to make the size you want. Lets say you want to fit a gun in it, you would drag the edge so the gun can fit in the shape you made with the polygonal lasso tool.
9. After you like what you made, you will hold ctrl and select the two layers and press Ctrl+E to collapse it.
10. Then use the move tool to move the picture you make, (The shape) and move it out of the way. Then erase the outside of it, and thats your final layer.
Then just repeat that for all the images you want.
Hope I helped
