Measure your baby’s head. This is how wide the neck opening needs to be. Measure your baby from shoulder to shoulder; measure around the stomach, hips and thighs. These are the width measurements. Measure from shoulder to wrist, from shoulder to stomach, from shoulder to hip and from shoulder to ankle. Measure from shoulder to underarm. Measure from crotch to ankle and from stomach to ankle. These are the length measurements.
On a piece of dressmaker’s paper, use a ruler to draw a rectangle as wide as your baby’s widest measurement, plus 2 inches for ease, and as long as you want the dress to go, plus 2 inches for the hem. Mark the length of baby’s armhole plus 1 inch.
Fold the pattern in half. Take half the measurement for baby’s head and mark it on either side of the fold line. For the front of the pattern, use the French curve to draw a rounded neckline. Decide if your dress will be drop sleeve or rounded sleeve. If it is drop sleeve, leave it alone. If it is a fitted round sleeve, take half the shoulder to shoulder measurement and, with the pattern folded in half, mark where the armholes should be on the shoulder, using the French curve to draw the underarm shape.
With your pencil and ruler, draw a triangle from the center of the neck hole, cross the bottom underarm mark and continue the length of the garment. This gives the dress an A-line shape. Your pattern has no waistline, so it is adaptable as your baby grows taller. It can easily go from dress to blouse.
Fold the dressmaker paper in half. Pin on the fold of the material and cut out the front of the dress. With the pattern still folded in half, pin to a double thickness of fabric and cut out the two back pieces of the dress. Don’t worry about facing, because the neck and armhole will be finished with seam binding.
Use a 5/8-inch seam up the back to within 4 inches of the neck opening. Use a 5/8-inch seam to close the shoulders. Use a 5/8-inch seam from underarm to hem. Stitch seam binding from one shoulder seam, around the neck, down the neck opening and up to the other shoulder seam. Turn the raw edge and hand stitch shut. Stitch seam binding around each armhole, hand stitching the raw edges shut. Turn the raw edge at the bottom of the dress and hand stitch a 2-inch hem. Attach a tie from the two lengths of grosgrain ribbon at the back of the dress.