I'm not sure if anybody has access to photoshop, but it's all I know so at long last, here it is in 10 easy steps!
1. open you chosen photograph in photoshop. I tried to pick a picture that had a good contrasting background (this was harder than I expected as all my photos seem to be taken with detailed backgrounds.)
2. Using the magnetic lasso tool (L) mark around the area you want to cut out, then double click on the layer to unlock it.
3. Once the layer has a name other than "background" you can delete the contents of the lasso and you will be left with a grey and white check where the background used to be.
4. Select "colour range" from the "select" menu.
5. From the drop down menu, select "highlights," and on a new layer, flood the selection with a pale grey.
6. Go back to "layer 0" and repeat for midtones, colouring with a mid grey on a third layer.
7. Go back to "layer 0" and repeat for shadows, colouring with black on a fourth layer.
8. Turn off the layers so that only one is showing at any one time.
9. Print each layer onto a separate sheet of a4 to create your templates, I found it easier to stack the applique from shadows (on the bottom) to highlights (on the top) and so that I didn't end up with any gaps. I printed the first sheet with all the layers turned on.
The second with midtones and highlights turned on.
The third with highlights only.
10. Then you can applique the shapes to your block using fusible fleece.
Let me know if you have any questions!