Dart

Fabric off the bolt is flat. Bodies aren't. A dart is how you reconcile the two — a wedge-shaped fold, wide at one end and tapering to a point at the other, that's stitched shut so the flat plane of cloth gets pulled into a curve. Bust darts, waist darts, shoulder darts, elbow darts — same idea everywhere, just aimed at a different curve.

The thing I had to unlearn as a beginner: darts point at the fullest part of the curve they're shaping, but they don't stitch all the way to it. Sew a bust dart right up to the apex and you get a visible pucker, sometimes a little pointy cone that looks nothing like a body. Stop a finger's width short and let the last bit of the point taper out on its own — thread tension does the rest.

I mark darts with a tracing wheel and dressmaker's carbon rather than pins-and-guess, mostly because I've been burned by a lopsided pair of bust darts before and I'd rather not repeat that.

How I do it:

1. Transfer the dart legs and point from the pattern with a tracing wheel.
2. Fold the fabric right sides together along the centerline, matching the marked legs.
3. Stitch from the wide edge to the point, tapering off the fabric entirely for the last inch rather than backstitching at the tip.
4. Press the dart flat first (as sewn), then to one side — vertical darts usually toward center front or back; horizontal darts usually downward.