One common pitfall when sewing is looking at the needle. This invites you to abruptly correct the steering, causing uneven stitches. Instead, look at the edge of your fabric and match it to the seam guide marks on the bed of your sewing machine. These provide a visual reference that stays still, helping you to maintain a consistent seam allowance. To test this out, pin a line on a scrap piece of woven fabric and sew over the line, try once looking at the needle and a second time with the edge of the fabric matching your chosen seam guide mark. Now see how much smoother that second line is by steering with subtle corrections only. Once you’re happy with the straightness of the line, press your seams and look closely at the width. How consistent is it throughout? This is the goal, it is more important to have a consistent width than a perfect stitch, as this will make it easier to join pieces together accurately.
Keep a light hand on the fabric as you sew. The feed dogs under the fabric pull the layers forward, so it’s just a matter of letting them do their work and gently guide the direction. Avoid pulling the fabric from behind, or pushing it as it reaches the presser foot. This causes the seam to stretch or bunch up and results in uneven stitch lengths. If the fabric starts to drift off course, correct with subtle adjustments rather than sharp corrections. If you try to force the fabric it will fight your corrections. Your hands should also have clearance from the presser foot, you do not want to try guiding right up next to it.
Control the start and end of the seam. This is where it’s common to speed up or go too slowly, as you only have a small amount of the piece under the presser foot, and are nearing the finish. These can be very noticeable in a finished item. If you make pouch covers, linings, or similar items, you may find them skewed or out of shape due to inaccurate seam endings. Slow down at the beginning and end, and backstitch if your pattern requires, taking a moment if your layers want to pull apart before the stitching has caught them properly.
Control pivoting points when sewing around corners. Stop at the marked point with the needle lowered into the fabric. This acts as a pivot point as you slightly lift the presser foot, carefully maneuver the fabric to the next side, and lower the foot. Without this you can get rounded seams. To practice, mark a square on your scrap fabric and where the seam allowance lines would intersect. This will tell you how far to sew before lifting the presser foot.
As you practice, draw three parallel lines on the fabric to help you sew with a consistent seam allowance. After each seam, measure the width from the edge of the stitching to the raw edge of the fabric. You want this to stay consistent. Once you’ve learned where to look, and where to place your hands, practice will help you to achieve the perfect seam.