Squaring up quilt blocks is not something I typically need to do. But with applique blocks it's the best way to ensure your blocks will finish at the correct size. Even the best of quilters can have some shrinking of background fabric during the applique process. So as a general rule applique background fabric is cut 1-3 inches larger than the finished size of the block then trimmed to the correct size after the applique is stitched in place. Most the time the trimming down is fairly simple process. Just press the block and square up to the correct size. This cute little dresden with yo-yo's will take a little extra effort.