I cut 2.5 inch squares if I can. Anything smaller gets tossed in my string bin. The strings are of various sizes and not always even from end to end. I foundation piece them into 9.5 an 3.5 inch blocks. My intentions are to make these blocks into a quilt with sashing using the 3.5 as cornerstones. I find making the string blocks addictive. When I'm in a blue mood I can set and sew string blocks without thinking.