Objective: Combine your threading, straight-stitch, and backstitch skills to sew a complete lined fabric coaster from start to finish.
A coaster is the ideal first sellable project because it uses every core skill in one small, forgiving piece. You sew two squares of fabric right sides together, leave a gap, turn it right-side out, and topstitch to close and finish. The key new techniques here are pivoting and the turning gap. To pivot at a corner, stop with the needle down in the fabric (press the needle up/down button on the MC6650 so the needle stays buried), lift the presser foot, rotate the fabric 90 degrees, lower the foot, and continue. The needle-down feature keeps your corner crisp. The turning gap is a 2-inch unsewn section along one straight edge; you push the fabric through it to reverse the piece so seams hide inside. Trimming the corners diagonally before turning removes bulk so points poke out sharply. A consistent seam allowance (use the 1/4 inch line on the needle plate) keeps the finished size even, which matters when customers expect matching sets.
Example: Cut two 5-inch squares of cotton. Place them right sides together, edges aligned. Set a straight stitch, length 2.5. Starting along one side, backstitch, then sew a 1/4 inch seam. At each corner, stop with needle down, lift foot, rotate 90 degrees, lower foot, continue. On the last side, sew 1 inch, backstitch, lift and leave a 2-inch gap, then backstitch again and finish the side. Clip all four corners diagonally. Turn right-side out through the gap, push corners out with a chopstick, and press flat. Topstitch 1/8 inch from the edge all the way around, which automatically sews the gap closed. Result: a neat 4.5-inch finished coaster.
Try it: Cut two 5-inch squares and sew a complete coaster following the steps: 1/4 inch seam, pivot at all four corners with needle down, leave a 2-inch gap, trim corners, turn, press, and topstitch around. Make two so you have a matching pair, and compare their finished sizes.