Preserving Memories of Four Generations

This is an idea that I first saw on Pinterest, but could not figure out how it was done.  I knew my Grandmother was coming for a visit, and that it most likely would be the last time I saw her since she doesn't live close.  I wanted to preserve the memory of the four generations together for the first/last time, so I thought I'd give it a go.  People have been asking me to post how I achieved the below picture, so here it goes:

First I took an individual picture of everyone outside with an empty picture frame (my Grandmother, my mother, someone took one of myself, and one of my daughter).  The picture was taken in front of the same background, and the colours we were wearing all related to one another (either black, white/beige, or red).  I then went into a computer program (I used publisher), and first put the picture of my grandmother on the page.  I then cropped each of the other pictures and layered them on top, inside the picture frames, until I finished with my daughters. The result is the picture below...it's not the final product, and I may seek some help from my Graphic Design friends, but it is possible to do yourself, and the result is a beautiful picture I will be able to pass on to my daughter.