Do you mean something like this:
Autumn Sampler . I don't think we have a tutorial, I just looked at a couple in the gallery and went from there.
I'd start with a square that you have a die for. I think I have variously used a 2" one and a 2 1/4" one, with the next size up for matting. I use a 9" square to place my 9 squares on, and find that scoring it at 3" and 6" to make a grid helps me place the small squares accurately.
Winter Sampler, ~this one used a 2 1/4� square for each piece, but only one matting layer.
Sampler Template
