Objective: Sew clean, straight, secured seams and pivot at corners on the Janome MC6650 — the three moves behind almost every sellable item.
Every product you'll make — tote bags, zip pouches, napkins — is built from three basic actions: a straight seam, a locked end, and a pivot. On the MC6650, select the default straight stitch (pattern 1) using the touchscreen; leave stitch length at the default 2.4mm for most sewing. To keep seams even, line up your fabric edge with an engraved line on the needle plate: the 1/4" line for quilting/small items and the 5/8" line for garments. Do not watch the needle — watch the fabric edge against that guide line, and the seam stays straight. Guide the fabric gently; never pull it, or you'll bend the needle and get wavy stitches. Let the feed dogs pull the fabric through at an even speed (use the slow speed slider while learning). To stop a seam from unraveling, secure both ends. The MC6650 has a one-step Lock Stitch button (the key-shaped icon) that ties off in place, or you can press the reverse lever to backstitch 3–4 stitches at the start and end. To turn a corner, stop with the needle DOWN in the fabric (use the needle up/down button so it's always down at corners), lift the presser foot, rotate the fabric around the needle, lower the foot, and continue. The needle acts as a pivot pin so your lines meet cleanly.
Example: Make a practice square on scrap cotton. Draw a 4" square. Start at one corner: lower the needle, press reverse and take 3 stitches back, release and sew forward along your line keeping the fabric edge on the 1/4" guide. About 1/4" before the next corner, press the needle-down button, stop with the needle in the fabric, lift the foot, rotate the fabric 90°, lower the foot, and sew the next side. Repeat for all four sides. At the final corner, backstitch 3 stitches to lock. You should have a crisp square with sharp corners and even stitch spacing.
Try it: Grab two scraps of woven cotton (about 6" squares). Stack them. Sew around three sides at a 1/4" seam allowance: lock-stitch at the start, keep the fabric edge on the 1/4" plate line, pivot (needle down) at each corner, and lock-stitch at the end. Then flip it and check: are the seams parallel to the edge, and do the corners meet neatly? Re-sew if your line drifted more than 1/8".