Sewing a 1/4" seams is extremely important when piecing blocks. Learn where the guideline for the 1/4" seam is on your sewing machine is. If there is none, make one with tape or stick-on foam. Some sewing machines have an adjustable needle position. Use this to help sew your 1/4" seam. Measure your units after you piece and press to make sure they are the right size.
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