I found some neat foundation block patterns over at Piece by Number and I understand the basic concept of how to do this but I don't understand what the A and B stuff means on the patterns.
I had to look at a few of their blocks before I found one with A's and B's. That just means to make the pattern in different sections and then join them. So you piece all the A's and set it aside. Then piece all the B's. When done sew A to B. Thanks for sharing their link - they have great patterns that can be used as fabric postcards as well as quilt blocks.
Hope this helps,