Tutorial: EASY Knit Baby Romper

by Kelsey Norwood

in Crafts,Sewing,Tutorials

Are you ready to make something easy and adorable? This is your project!

Like I said yesterday I love rompers but my babies are just too darn tall to wear them from the store. But that’s okay, because rompers are suddenly one of my favorite apparel items to make.

If you missed yesterday’s post, check it out. You’ll need it to make your own knit romper pattern.

Made it yet?

Good. Let us begin.


First of all, choose a knit. I’m using a new Michael Miller cotton/poly/spandex jersey knit. It’s nice and stretchy, so comfortable for the little babies.

Cut out the four pattern pieces (front, back, front and back crotch) AND some ribbing (cotton/spandex blend usually) for the neckline. 1.5″ x wof is just about right.

Mark the shoulders with dots (should be on your pattern, transferred from the original onesie pattern). I like to mark with an air erasable pen on the wrong side of the fabric.

Serge the leg openings and the sleeves.

I’ve finally discovered how to hem knits – cut a strip of 3/8″ hem tape long enough to go along the bottom edge of the sleeve. Cut it in half so it’s only 1.5/8 wide and press about 1/2″ from the bottom edge. Remove the paper backing, fold the hem up 1/2″ and press in place.

THEN stitch with a double needle. This is the only way I can get my double needle hems to look normal on knit fabric. It does take a few extra minutes, but it’s definitely worth it.

Serge down both sides of the ribbing, press almost in half (leave one side just slightly longer so you are sure to catch it when you stitch it on), and pin along the neckline of both the front and back pieces.

Stitch two lines on top of the serging either using a double needle or sewing two separate lines of stitching. Both stitching lines should be within the serging, so pretty close to the edge.

Lay the front piece down on the table face up. Lay the back piece on top, also face up, and match the shoulder dots.

Pin the sleeve in place (there should be marks on the pattern to help you line everything up right) and serge the sleeve and the overlapping front and back pieces all at the same time. I usually serge this seam twice just to be safe.

Almost done!

Mark the crotch pieces (B for back, F for front, it makes a difference) so you don’t get confused. Pin them right sides together and serge around the two short ends and the longer curved edge.

Turn right side out and press flat.

Match the back crotch piece up to the back romper piece and the front to the front and serge the seams.

Now it’s time to sew the snaps in, and Snap tape is the only way to go.

You can purchase individual snaps, but this snap tape is amazing. It’s SO EASY and it’s not going to tear a hole in your knit fabric when you try to undo them.

The snaps are already positioned (perfectly, by the way…) on twill tape. It’s sturdy, it’s strong, it’s my new favorite thing.

Cut about 6″ of snap tape or a piece with 4 snaps and a little bit of extra on the ends.

Flip the front crotch piece to the inside and pin the snap half with the holes in the middles to the crotch pieces. You’re going to sew the snap tape to the crotch piece to the romper front all at the same time.

Getting this to look professional is tough because you’re sewing twill tape, which doesn’t stretch at all, to a curved stretchy piece of knit fabric. My consolation is that it’s on the inside and hopefully no one will ever see it. Unless they’re changing that baby’s diaper and then they’ve got bigger things to worry about…

Sew the other half of the snap tape (with the pokies in the center) to the back crotch piece. Don’t sew it down to the back romper piece, it should flap freely.

The last step is to serge from the sleeve all the way down the side seam to the leg opening. I serge this twice too, just in case.

And that, my friends, is a romper made by you!

{ 1 comment }

1 Robin March 5, 2013 at 6:53 am

Thank you so much I just bought the onesie pattern M6344 and wanted to make a Romper for my son. You have helped me save time and possible mistakes!

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