I am making my quilt bigger so will be adding about 7 more squares. Also I didn't have a layer cake or jelly roll so I cut all my pieces. I kept the strips for outer borders in one pile and inner borders in another pile.
Then I sewed all the inner borders first onto the squares doing 3 and 4 squares at a time to keep track of the fabric.
The hardest part is getting them laid out to look like they are stacked. Still working on this on the spare bedroom floor.