My 2.5" squares were organized in stacks, which were sorted by color and fabric. I started by reorganizing them into groups based on quantity. If I only had 1-3 squares of a fabric, it went into the group of fabrics that could only be used for the center ring. If I only had 4-7 squares of a fabric, it went into the group of fabrics for the inner ring. If I had 8 or more squares of a fabric, it went into the group of fabrics for the outer ring. Of course, the fabrics for the outer ring could also be used for the inner rings as well, and quantities left changed as I committed them to a block. I picked one fabric for the center, and coordinating groups of four and eight fabrics for the next two rings. Each group became a little pile.
Once I had enough piles, I laid them out to eliminate having similar fabrics too close to each other and labeled the piles with their location in the layout. I label rows with letters and columns with numbers - A1, B2, etc. - which I'll refer to as "'blocks" even though they won't be independent units.
|Piles of fabric squares
The white squares for the interior were cut to 2.5". The white pieces that would be on the edges of the quilt were cut 2.5" x 3" to make sure I'd have enough overlap to trim the edges and accommodate the binding.
Note: Below is an example of a center row. The top and a bottom rows will be different because you will need to use the rectangular pieces to create the top and bottom edges of the quilt. Where the strips of 2 and 4 squares connect to the other strips of 2 and 4 squares, always use squares, not rectangles.
I laid out each "block" at the beginning of the row and sewed them together, using the longer white rectangles on the ends that would become the edge of the quilt (the three on the left in the photo below), and the white squares on the ends that would connect to other strips (the two on the bottom in the photo below). This created a strip of 2 squares, a strip of 4 squares, a strip of 6 squares, another strip of 4 squares, and another strip of 2 squares. Then I moved the first three strips with 2, 4, and 6 squares into a pile off to the side, keeping them in order.
|First block in a row (left end)
I took the second strips of 4 and 2 squares and laid out the next "block" in the row, ultimately turning them into strips of 6 squares as well. This process repeats through the end of the row. Move the three strips with 6 squares on to the piles of strips, keeping them in order. Take the last two short strips to start the next block.
|Middle block in a row - all the white pieces are squares
When you get to the last "block" in the row, add the longer white rectangles that will create the edge of the quilt (the three on the right in the photo below).
|Last block in a row (right end)
|All the squares of a middle "block" sewn together into strips
and labeled with "block" location
|All the strips for one row, labeled and in order
|Piles of strips for each row of blocks
Once you have two rows of strips, you can start connecting the strips. Your first three strips will just be one "block." (As you can tell from the photo below, you'll also need to add a strip of white to create the corner of this block.) You will only be able to connect the first three strips of the second row before you also need strips from the third row, so you may want to wait until you have several rows of strips before you start joining them. In the photo below, the next strip to be added involves strips from A6, B5, C4, D3, E2, F1. Then you just keep on going. It can get heavy as you add strips, so you may want to piece in sections as the strips get longer and then join them.
See the finished product.