9 Tips for Pressing Seams When Sewing Garments

Pressing seams is an incredibly important part of the sewing process. It’s one of those skills that can level up your sewing with very little extra effort from you. But, of course, it’s not always as easy as it sounds. When most people hear about pressing seams, they immediately assume it’s the same as ironing. But that’s not really the case. Ironing is about getting rid of wrinkles while pressing is about creating creases.

Generally, when I press seams while sewing, I will first press them on the wrong side, then turn the fabric over and press the seam on the right side as well. This ensures that you have a nice, tight seam when you see it from the front.

When pressing garments, you want to press down on the iron to create pressure to hold the seam in place. You can use a press cloth or steam to help, but the main factor is the pressure, that’s why it’s called pressing. 

1. The difference between ironing and pressing

Generally, when people talk about pressing garments during the sewing process, it’s a completely different skill than ironing a finished piece of clothing. Pressing is more of a targeted action where you need to use pressure to get the seam to sit right while ironing is more about loosening the fabric with heat so it can be spread flat.

Pressing is all about applying pressure and heat to a seam in order to force it to stay in place. To some extent, you are purposefully pressing a crease into the fabric as you fold the seam around the stitch line. Think about it, even though you’re flattening a seam, you are actually creating a crease on each side of the fabric.

Ironing, on the other hand, is about getting rid of visible wrinkles by smoothing out the surface of the fabric. It’s the opposite of what you’re doing when trying to press the seams of your garment.

2. Always press seams as you go

Whenever you sew a seam, you should immediately move to the ironing board and press it. You do not want to wait until the garment is completely finished to go back and press everything, since that will not give you the same results.

To clarify, it’s okay to sew the two side seams or two shoulder seams and then press them all at once to save a little time. What you want to avoid is any kind of crossing seams. So you can sew your side seams and shoulder seams, but then you have to press them before adding your sleeves.

I know this is quite tedious. To make things a little easier, I make a habit of setting up my ironing board right next to my sewing machine every time I sew. This way I have my sewing station and can immediately move to my ironing station as soon as my new seam is finished.

Most of the time, this is not included in the step-by-step directions of a sewing pattern. It’s considered basic knowledge that everyone theoretically already knows how to do. But if you’re completely new to sewing, you might not know that you’re supposed to press the seams as you go.

3. Wiggle the tip of the iron along the seam

Instead of relying on the entire face of the iron, it’s useful to learn how to use only the edges and triangular tip of the iron when pressing seams. What you’ll want to learn how to do is use the tip along the seam. Press it, then slightly wiggle it forward to open the next section of the seam. Then press that and continue down the length of the seam line.

If you’re working with a closed seam, you’ll want to use the edge to just slightly push and press the seam allowance away from the seam, staying as close to the seamline as possible.

Think of it this way: the flat of the iron is for when you are ironing garments to de-wrinkle them. The tips and the edges are for pressing seams.

4. When necessary, use a pressing cloth

Some types of fabric are highly sensitive to heat. Polyester, for example, has a fairly low melting point. If you use a hot iron, the fibers will begin to melt into an ugly blob. Normally with these fabrics, you use an iron on the coolest settings. But sometimes this isn’t hot enough to press the seams.

In this case, the best thing to do is use a press cloth. Typically, you would use a length of cotton or another material with a high heat tolerance. Place it over top of the polyester (or silk, rayon, etc.). Then you can increase the heat of the iron and press the seam while the press cloth covers it.

If you’re still struggling to get your seam to lay flat, you can also spray your press cloth with water. When you use your iron again, the water will turn into steam and aid in getting your seams to lay nice and flat.

5. Press on the reverse side and then again on the front

While most traditional sewing advice I’ve seen says to always press the seam from the back of the garment, I have found the best method is twofold. 

1. First, as recommended, I will press the seam with the garment facing inside out.
2. Second, I will turn the garment right side out and press the seam again.

This always helps me get a much flatter seam than what I can get just pressing it from the back. That being said, you have to be careful using this method, especially if you’re using a fabric that’s sensitive to heat. Make sure you’ve tested your iron settings so that you don’t burn or melt the fabric.

6. Go back and iron the area underneath the seam

With some types of fabric, particularly thin fabrics, you’ll get a slight imprint of your seam or dart on the right side of the garment after you press the seam. If this happens, you can go back and iron the fabric that is underneath the seam to remove the imprint. It’s best to wait until the fabric cools down before going back to re-iron the area with the imprint.

7. Pay attention to the seam direction

When you are pressing your seams, it’s best to press them toward the direction that has less bulk. For example, if you have a gathered waistline seam, you want to press it up toward the waistband or bodice.

If neither side of the seam is bulkier, you can choose to either press the seam open or press it toward the back of the garment. This is the direction that seams are typically pressed:

• Shoulder seams: toward the back of the bodice.
• Waistband: Up, toward the bodice or waistband
• Bust darts: always press these down
• Vertical waist darts: these should be pressed toward the center of the body
• Armhole seams: Toward the bodice, away from the arm.
• Side seams: Toward the back of the body.

Learn more about which way to press seams and what the exceptions are

8. Use pressing hams to press seams on curves

I don’t know how I pressed anything before I got my pressing hams (also called a tailor’s ham). These are basically firm pillows (sort of) that give you a variety of curved surfaces to use for pressing all kinds of seams. 

These can be used between layers of fabric so you don’t have to worry about causing wrinkles into the back of the garment while you’re pressing the front. There is also no better way to get neckline seams pressed on a curve. The longer type of pressing ham (sometimes called a tailor’s sausage) is the only way I know to get armhole seams pressed thoroughly. 

If there is any sewing tool that I recommend every sewist has, it’s a tailor’s ham (other than a sewing machine and iron, of course). This is the set of pressing hams that I got, and it’s been a wonderful tool for me.

9. Pre-press the seam with your fingers

The iron does not have to do all the work when you are pressing seams. It helps immensely to pre-press seams with your fingers before you go over them with the iron. This makes it more likely the seam will flatten correctly, without accidentally catching a small amount of extra fabric folded along the seamline.

1. To do this, rub your fingers together so that your fingers are a little warm. 
2. Then give the seam a preliminary press using just your fingers.

This type of finger pressing is especially useful along any kind of curved seam and along necklines and armholes that require facing or bias tape.