It is difficult to find the right pair of jeans. You may have almost-perfect jeans that are too big in the waist. Sewing in darts fixes the problem. With a few easy steps, you can tailor your jeans to fit your unique body shape by using the right size and number of darts. Darts are triangular tucks that are wide at one end and tapered at the other. The darts take up all the extra looseness in your waistband like a tuck.
Turn the jeans inside out. Put them on so you can determine how much to take in. Pinch the material at the waistband. Adjust so they feel comfortable, and then use pins to hold. Take them off to prepare for darts.
Draw the dart. Using a washable fabric pen or tailor's chalk, draw two lines for each dart -- starting at the waistband pinch points and intersecting a few inches below. Add a third line down the center of the two lines. Use a ruler for more precision. Your markings should look like an elongated triangle with a center line. Remove all the pins.
Fold the jean fabric along the center line, with the right sides together. Line up the outer lines, and secure the dart into place with a loose stitch or basting.
Stitch the dart into place. Follow the marked sewing lines. Sew from the widest point to the most narrow for best results. Cut the top and bottom thread after the stitching is done. Leave at least 4 inches of thread at each end so you can knot the dart into place. Be careful not to pull too tightly or you risk puckering the material.
Iron the dart, using a medium hot setting. Press the dart flat with the fold at the center. Press down with the iron, moving from the widest point to the most narrow. Stop at the end of the dart, so you don't crease your jeans.