3133 Onesie - Tips for an easier construction

Pattern 3133 uses different binding techniques, which can be a bit tricky (and may require a few coffees). This post simplifies the process by using a consistent binding method throughout and clarifies the placket construction. 

Neck and sleeve binding

First, to make the binding method uniform, widen the neck and sleeve binding pieces. Widen by 6 mm (¼'') : 

Pin the right side of the binding to the wrong side of the sleeve, matching notches :

Press the seam allowance toward the sleeve. Fold the binding wrong sides together, bringing its raw edge to the seam, and pin :

Bring the folded binding to the right side of the sleeve, covering the seam allowance, and pin :

Topstitch using a zigzag stitch, double needle, or cover stitch.

Use the same technique for the neckline : 

Clean finish inside and out : 

Leg openings

Pin the right side of the binding to the wrong side of the onesie, matching centers and letting the binding extend 1 cm (⅜") beyond the front edges.

Close up of the binding ends at the front : 

Stitch and press the seam allowance toward the garment :

Fold the binding wrong sides together, its raw edge against the seam, and pin :

Bring the folded binding to the right side of the garment, covering the seam allowance, and pin :

At the corners, gently pull the binding so it aligns with the front edge :

Topstitch using a zigzag stitch, double needle, or cover stitch :

Snap placket

Apply non-stretch fusible interfacing on one half of the placket : 

Fold right sides together and stitch across ends :

Turn right side out and topstitch : 

Pin placket to front, raw edges together : 

View from wrong side. Notice how the placket width matches the width at the seam line, 6 mm (¼'') from raw edge : 

Stitch and finish the seam allowances, if desired, with a serger or zigzag stitch :

Bring placket away from the garment, hide tails under the seam allowance and topstitch :  

Apply snaps to the placket and back : 

Voilà! We hope this makes things a bit simpler and gives you the confidence to sew custom onesies. It’s also a great pattern for upcycling old adult T-shirts for little ones!