Mat your photo the color of your choice.Then right click on the photo and left click on Copy. Now right click and then left click on paste. You will have two of the same thing.
Remove the mat off of the copied photos. Click on Tools and choose your paper or color to fill the photo box. Then make it slightly larger than the photo. You will then need to place it under the photo by left clicking on the second photo box in the element panel and dragging it under the original photo.
You now have a double mat photo and you can choose Tools and use a heavy shadow to make them both pop off the page.