For a rounded hem, like on a circle skirt, a simple fold-over won't work. Try it on a scrap… when you fold over the edge, the extra fabric puckers up. What to do? 

Don’t panic. We’ve pulled together a few great tricks for sewing a neat curved hem. Some will work for other rounded edges too, like neck openings and ruffles.

Keeping the hem extra narrow is the trick here. A narrow folded hem is great for finishing very fine fabrics like chiffon, georgette, habotai, and charmeuse.

This type of hem is known as a narrow folded hem, a rolled hem or a baby hem.

The trick is to start with a very narrow hem, less than a quarter of an inch (a few millimeters). The puckers never get a chance to form. There are two methods.

The first method is to sew the hem three times, and for very fine fabrics it may be too bulky. If that’s the case, try changing to extra-fine thread or use the next method, where the hem is sewn only twice.

This technique is relatively quick, so it is great for times when you have to finish lots of edges for layered skirts or ruffles.

To avoid weighing down the hem with three lines of stitches, skip sewing in the first step, and fold over without a baste line to guide you.

Finishing a hem with bias tape looks neat and works well for most fabrics, especially those with a medium to stiff drape like cotton or linen, habotai, dupioni, brocade, and duchesse. For a circle skirt hem this method adds a little stiffness and makes the skirt look fuller. A bias tape finish will work for any curved edge in a garment – neckline, sleeve opening, etc.

You can cut bias tape from your main fabric or buy one pre-made. Most fabric shops carry a range of colors in cotton or polyester satin.

Finishing a hem with crinoline tape (or horsehair braid) yields a classy look that works especially well with stiffer fabrics like duchesse and taffeta. It stiffens the hem and makes the skirt look fuller. Note that a hem finished this way tends to buckle slightly.

Crinoline tape is bendable, so it is a natural choice for rounded hems. It is sewn to the fabric a short distance from the edge and then the edge is pressed back over the tape and stitched on by hand or machine.
 

If you are sewing with a shrinkable fabric that can be pressed with a steam iron on high heat, this is a great little trick. It works with cotton and linen plain weaves, rayon, wool, and some silk fabrics (noil, spun silk, some of the heavier wild silks). This method can work for any curved edge in a garment – hem, neckline, sleeve opening, etc.

Aside from a steam iron, you’ll need a heavy paper template. Cut a piece of craft paper into a shape that follows the fabric edge.

You can finish the rough edge before you begin with a zigzag or overlock stitch. Then fold the fabric edge back over the template and press using the steam setting. Sew in place by hand or machine. For fabrics that really press well, you can roll over a narrow strip along the rough edge before folding over the wider hem for a more finished look on the inside of the garment.

The overlock stitch available on a serger machine is the quickest way to finish a curved edge, but it won’t work for projects where you want a neat, professional finish.

That said, this method saves a lot of time in places where you don’t need a perfect finish.

The exact setting differs from machine to machine. For finer fabrics, use a narrower, denser stitch. If you set the stitches too far apart, the fabric will tend to fray at the curves.

For beginners, test on a scrap first. Then you can play with thread tension and decide if this is the look you want or if you should use another method.